Even though you know you need eight hours of sleep a night, you probably sleep much less than that. Me, too. Tonight, for example, when I should have been going to bed I made cupcakes for my son's classroom. I was so tired that I doubled the amount of sugar, and baked them anyway. They came out squishy from so much sugar, but, per my son's request, I added green frosting and silver sprinkles on top anyway. I said to myself, “These are absolutely the most disgusting cupcakes ever.” Then, two hours later, when I feared I was too tired to stay up to write a column, I ate three cupcakes.

I told myself I would never stay up late for work again. But then I worried that I was probably lying to myself. So in an effort to really reform myself I have constructed a list of things to remember next time I see the clock strike 10 p.m. and I make no move to go to bed.

1. Sleep deprivation makes you act drunk. Occupational and Environmental Medicine reported that if you stay up for 18 — 20 hours in a row, your mental capacities are the same as those with a blood alcohol level of 0.1 percent, which is the legal driving limit.

2. You are smarter if you sleep enough. Scientists at the University of Luebeck found that when you sleep eight hours you solve problems that you cannot solve when you have not slept enough. So pulling an all-nighter seems fine, if you don't have to be smart the next day. But a lot of sleep-short nights mean a lot of stupid days. And sooner or later, it won't matter if you have the capacity, somewhere, to be brilliant. If you don't ever exhibit it because you never sleep, then for all intents and purposes, you are a slow thinker.

3. Creativity happens after a good sleep. Maybe the manic can get away with no sleep, but for the typically calibrated worker, sleep allows the brain to synthesize in ways that precede a great idea. Dmitri Mendeleev came up with the periodic table of elements by dreaming it. And Laurie Halse Anderson won a National Book Award Nomination for Speak, a book she dreamed and then woke up and wrote.

4. People who don't sleep are in denial. I have heard so many people say, “I don't need eight hours.” Okay. Fine. You need seven. But unless you're over 65, you need at least seven hours. You lie to yourself when you say you don't need the sleep, and the person who is hurt by the lie is you, because you never allow yourself to be your best self during the day. You never get to see what you can really do.

4a. I, by the way am not one of those people who says I don't need sleep. I always want more sleep. But I'm still in denial. I am in denial all day, leading up to the sleep deprivation. I have opportunities to get the most important stuff done but instead, I do easy, unimportant things, like answer random emails. I keep saying to myself, “I have time, I have time.” But I don't have time. Not if I'm going to get eight hours sleep.

5. The just-before-sleep part is magic. One of my favorite sensations is lying down to sleep but not falling asleep right away. My mind clears up, and I see all kinds of things that the tumult of the day obscured. Lying on the pillow with nothing to do is a luxurious feeling. But if I'm not getting enough sleep, that time is gone; I fall asleep the second my head hits the pillow.

Like all good addicts, I am telling myself, as I do this sleep deprivation thing tonight, that I'll never do it again. But really, I think getting enough sleep takes a huge commitment. You need to reorganize your life so that when it's time to go to bed, you've finished all the essentials. And you need to make getting enough sleep and essential. I say “you” because I'm not quite sure that I'm there yet. But now at least I have a list of reminders for next time I see my bedtime slipping by.

All managers have one, shared goal: Get a promotion. But many times, the job of a manger is so multifaceted and detail-laden that the manager loses site of that big picture. Here are five jobs of a manager that are often lost in the muddle of managing smaller, day-to-day issues.

1. Manage conflict
Avoiding conflict is for people who want to lay low and move up by dint of inertia. This plan will take you only so far. At some point you have to meet conflict head on and show that you can resolve it. Think about this: At the highest levels of management, leaders are essentially gathering competing opinions from the very informed and making a decision based on conflicting recommendations. Conflict at your level, e.g. “Karen is late on every project and I don't want to work with her on the next one,” is preparation for the next level. Don't shrink from this stepping-stone by hiding in the sand until the conflict resolves itself. Managing conflict allows you to become an arbitrator and negotiator, and most of all, someone who has developed good judgment on hard calls.

2. Manage your personal life.
You are kidding yourself if you think people don't see what's going on with you at home. Are you getting drunk every night? Are your finances a mess? You might live a fantasy that you are hiding bad behavior from co-workers, but stress shows up in nonverbal, unexpected ways that make people uncomfortable to be with you and worried about your competence. People who seem to have shaky lives at home seem like time bombs at work. So instead of trying to hide your personal life, redirect that energy toward improving your personal life. You might not have as much focus for work in the short term, but in the long term you'll be in better shape to manage effectively.

3. Manage hearts and minds
Sure, you need to manage budgets, schedules, and strategy. But if you don't have peoples' hearts on your side, your team won't over perform for you. The easiest way to win the hearts of your team members is to genuinely care about them. You can't fake this. So if you don't genuinely care about people who work for you, ask yourself why you are in management. (There are plenty of big, rewarding careers that don't include management.) Management is about helping people to be their best. Once you genuinely care about people, you will be able to find out what excites them, and you will help them reach their goals at work. Which, invariably, will shine favorably on your own workplace performance.

4. Manage diversity'
Diversity is not popular right now, when so many people worry about their job going overseas. But study after study shows that diverse teams perform better than homogenous teams. And besides, diversity doesn't mean hiring someone in Mumbai. Managing diversity starts by hiring someone who is not like everyone else on your team. Then do it again and again and find a way to make the team gel. Diverse teams are more difficult to manage — there are more opinions, more preconceptions, more quirks, and more conflicts. But top managers can leverage these difficulties as a means to establish more innovative planning. After all, no one became great by surrounding themselves with people who think like everyone else.

5. Manage a successor
If you're doing a good job, it's hard to convince your boss to promote you; he has no idea who will take your place, and he risks his own job performance by letting you replace yourself with someone who might not be as capable. Instead, train someone in-house to take over your job as soon as you have a handle on it yourself. The person should be practically doing your job so that you can find areas where you can take on more responsibility before you ask for a promotion. Managing a successor allows you to first lead without the title, and then to ask for the new title. And more money.

Those who have mentors are twice as likely to be promoted as those who don’t, says Ellen Fagenson Eland, professor at George Mason University and 2003 Winner of the Mentoring Best Practices Award. So start taking the mentoring process very seriously — it should be a cornerstone of your overall career strategy. Here’s a plan to get you started:

Step 1: Identify a potential mentor. This person can be any age, but the most effective mentor is someone approximately five years ahead of you in your career. A person at this level will know how to navigate your organization at the spot you’re in, and the person will remember what it is like to be where you are. This person should be someone you admire and someone who has good communication skills.

Step 2: Have good questions. Would-be mentors are most receptive to people who ask good questions. What makes a good question? It should reveal that you are both directed and driven. But the question should also demonstrate that you understand the mentor’s expertise and you can use it well. So, a question like, “What should I do with my life?” would be out.

Step 3: Don’t expect miracles. A mentor is not going to rescue your whole career, even if she can. People want to mentor a rising star, so look like you’re on track when you ask for help. Ask, “What skills should I develop to earn an education policy analyst job with a Senator?” rather than, “Can you get me a job with a Senator?” even if the mentor is Caroline Kennedy.

Step 4: Be a good listener. This person is not your therapist. You ask a question, and then listen. If the mentor needs to know more, he’ll ask. Do not tell your life story. It is not interesting. If it were, you’d be writing a book or doing standup, right? If you find yourself talking more than the mentor, then get a therapist before you scare your mentor away.

Step 5: Prove you’re serious. You can demonstrate that you’re hungry for counsel by implementing the advice your mentor gave, showing the result, and then going back for more. So, if your mentor suggests you get on project X, get yourself there, do a good job, and report back to your mentor that you are grateful for the advice because you were able to learn a lot and shine. Your mentor will be much more willing to give you her time and energy after you’ve proven yourself to be a quick and eager study.

Step 6: Always be on the lookout. One is not enough. Each person needs a few mentors, because no mentor lasts forever, and each has a different expertise. Two of my best mentors were very different from each other. One helped me to fit in with the guys so that I could succeed at a company where I was the only woman in management. Another mentor helped me to keep my sanity and my focus when balancing work and children seemed totally impossible.

Step 7: Give back. The best way to learn how to rope in a mentor is to be a mentor yourself. You’ll find out first hand what makes a protégée annoying, which will, in turn, make you a less annoying protégée. You’ll also discover why helping someone else grow is so rewarding, which will give you the courage to ask people to help you.

Even though I rarely tell you about the letters I receive from readers, I do receive a lot of mail. Almost all of it is thoughtful and intelligent, and the mail does influence what I choose to write about. Many times I answer questions directly, but today I'm going to answer a reader email in the column. My hope is that if you see how I answer a question, then you can answer your own questions using a very basic but tried-and-true Penelope formula.

The woman, I'll call her Darcy, wrote that she is a PhD who was hired to do research and present numbers to the Board of her company. The letter is much longer than that one sentence, but the basic point is that the board was getting inaccurate numbers from a lesser-qualified person so the board hired a PhD to make sure the information was completely accurate. Fair enough, especially in the wake of Enron and Aon and all the other number-hiding companies that crashed in recent history.

The problem is that, according to Darcy, the board is frustrated by Darcy's inability to come up with a way to present the numbers that the board likes. And Darcy is frustrated by the board's need to have numbers that are not exactly what she comes up with. After all, wasn't she hired to come up with the truth?

Here is some insight into how Penelope thinks: I look at the letter and say to myself, why is this Darcy's fault? You might think, Penelope you are so unreasonable to always blame the letter-writer. But face reality: You are not going to make a board change. You're not going to make a boss change. The people who write letters to me are generally having trouble with people who are not going to change. So there's no point in saying, “Wow, you sure do work with difficult people. Sorry. Love, Penelope.” Or, worse yet, saying, “Yes. This is a very bad situation. You should quit. That'll really teach your company a lesson. Good luck with unemployment. Love, Penelope.”

The best advice I can give is how the person with the problem can solve the problem herself. In the case of Darcy, she needs to recognize that she has an impossible job. There's a reason why very few Ph.Ds are CEOs. The former is all about detail and accuracy. The latter is all about big-picture and spin. Not that both titles don't require big picture AND accuracy, but very few people can focus on big picture and accuracy at the same time.

Probably, Darcy is never going to be able to re-jigger numbers for public relations spin. My first advice would be for her to extract herself from the spin part of the job — give the numbers to a public relations person before the numbers go to the board, for example. But maybe Darcy really wants to step up and deliver the numbers in a way that the board wants. In truth, people who can juggle details and big-picture go very far in corporate life. So maybe Darcy can do this, but then she needs to stop complaining about what the board wants, and learn to deliver it. Let the board decide if it's proper or not. (Note to ethics mavens: Darcy is definitely at the beginning of her career and in no position to be questioning her board's ethics. She would be ignored and then fired.)

But let's take a step back. Because almost all of my “What should I do?” emails from readers are like this one. When you have a problem with how other people in the office are treating you, figure out how you can change. When you have a problem with how people want you to do your job, change your approach, or change your job description, but don't blame someone else for what they want. This is not going to get you anywhere.

People in corporate life get promoted for their ability to take control of a problem and solve it. If you cannot take control of problems within your own job, you are not going to persuade people you can take care of corporate problems. So on some level, you have to look at your problems like I would look at your problems: Blame yourself first.