High performers work for free.  The difference between working for free because you’re a loser and working for free because you’re a high performer is what you get from the deal.

People often ask me how to become a writer. The answer is to write for free. You won’t get paid for years. I wrote for decades before I saw any money from my writing.

Here’s how to decide if working for free is a good idea for you:

1. Can you reach your goal without working for free?
If you are aiming to do something that people don’t really like doing, then there is no point working for free. Whoever is hiring is grateful to have you. Child protective services, for example. It’s an impossibly difficult job—low pay, high stakes, and your hands are tied, even in some of the most difficult cases.

But you know how you can tell when it’s a job no one else wants? It’s really easy to get. If you are having trouble doing the work you want to do then it’s a pretty good bet that it’s not easy work to get.

All other jobs—the jobs that people genuinely want to have—are candidates for free labor.

2. Is there a path to payment?
People can bitch about unpaid internships and how illegal they areOr they should be. But in general, companies offer unpaid internships in fields where there is a clear path to payment and there is high competition to get on that path.

Often, if you are able to get an unpaid internship, or grossly underpaying internship, you are lucky. There are not a lot of sure things in the work world, but sometimes, employment after an unpaid internship is an almost-sure-thing because the internship is so prestigious.

Proofreading at the New Yorker, for example. Or clerking for a judge.

When I first met Melissa, she was working for National Geographic as a photographer, and she offered to take photos of my kids, for free, for my blog. (There’s one of her photos at the top of this post.) She could see — way before I could, actually — that her photos published on my blog would lead to tons of freelance work for her taking photos of other peoples’ kids.

3. Are you making a good connection for your network?
Some people are magnets for opportunity and success. These are people who are known for taking someone under their wing and helping them fly. These people have great ideas and great connections to make those ideas happen.

Often, working for free with someone like this enables you to have a long-term connection with this person so that years after you are the underpaid underling, you can come back to get real help and real money because you made a real contribution to the person when you worked with them.

Don’t kid yourself—people who are well connected get offers every day from people who will work for free. It’s a trick to sift through these offers to figure out who will be a pain and who will be helpful.

Also, when it comes to offering to work for someone who can do a lot for you, figure out a project you can do that will immediately benefit that person, and if you do a good job, they are likely to pay you for the next one—or recommend that someone else pay you. Either way, you’ll get paid.

4. Are you building your resume?
Justin Kan points out, on TechCrunch, that one of the best ways to get a job you are not qualified for is to just make something that is related, so that you are qualified. It’s working for free, for sure, but it’s building your resume, whether the thing you make is successful or not.

Do you know the biggest mistake people make when they work for free? They don’t know how to translate it onto their resume. Work experience is useless when it comes to getting you your next job unless you can translate that experience onto your resume.

So when you start working for free, you need to have a very clear idea of how you are going to describe this work in your resume.  Loft Resumes has a great explanation of how hiring works: There are two piles—save and toss—and the reader spends 30 seconds, tops, looking at your resume to make the decision. You need to format your resume so the hiring manger sees your did-it-for-free experience right up front. That’s how the work will pay off, by getting the next job.

Often people hire a professional resume writer to format their resume to achieve this goal, but if you don’t want to pay that much money, Loft Resumes is good at helping you format your resume to draw attention to the right thing during those thirty seconds.

5. Are you getting to try something new?
Working for free never ends. Even when you are at the top of your field, you will find opportunities to work for free, or nearly free.

Lately, I am doing that with my writing. I don’t write a lot about the nuts and bolts of startups on this blog because I think that often, the topic is too specialized.

So I am writing about startups for Venture Beat, which is a great outlet for startup news. Here’s the link to my first article. Maybe you will like the topic. But even if not, the article might inspire you to find your own best bet for being underpaid. Because unpaid work for personal growth is a good idea no matter where you are in your career.