Time to negotiate for a raise? Here’s how.

April 25, 2013, 6:38 PM UTC

FORTUNE — Dear Annie: The article that appeared on your site about Gen Y women closing the pay gap resonated with me, because I am a 26-year-old female e-commerce manager making about 20% less than I’m worth on the open market — at least, according to all the research I’ve done (and two recruiters I’ve spoken with). What happened was, I accepted this job at a low salary in 2009 because I had only about a year of experience at that point and because, in the worst of the recession, I felt lucky to be working at all.

Since then, I’ve expanded our business significantly, hired and trained some real stars, and made other important contributions, but I’ve still gotten just the standard 2.5% annual raise everybody here gets, and I think I deserve more. I love working here and would rather not leave, but my negotiation skills are not so great, and budgets are still tight. Can you recommend any specific things to say to my boss, or not say? — Just Jill

Dear J.J.: You’re not the only one who’s “not great” at negotiating. Regardless of their position, 36% of men say they “always” ask for more money when they feel they’ve earned it, says a recent poll by Salary.com — which is more than the 26% of women who say they do, but still hardly a majority.

Moreover, it seems that tech professionals (including e-commerce managers) leave $4,300 or more per year on the table by accepting the first offer a hiring manager makes, according to a new report from tech job site Dice.com. National average pay for techies is $85,619, and, says this poll of 838 hiring managers, most candidates would get at least 5% ($4,300) more if they just asked for it. Only 18% of the managers surveyed said their initial offer is set in stone.

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“The only explanation for the lack of haggling is fear,” observes Tom Silver, a Dice.com senior vice president. He suggests that people calm their nerves by keeping in mind that “a negotiation is simply a discussion aimed at reaching an agreement, which both sides want.”

That’s especially true since, from your description, you sound like someone your company would prefer to keep around. “But attitude is key,” says Stuart Diamond, who teaches a popular course on negotiating at The Wharton School and wrote a book called Getting More: How You Can Negotiate to Succeed in Work and Life. “Going in as the injured party and being negative will not work. You have to be positive and upbeat.”

You also have to be “collaborative,” he adds. “Be ready to acknowledge, at some point in the conversation, that budgets are tight. Say something like, ‘I know it must be tough for you with so many people wanting more money.’ The last thing you want is to make your boss uncomfortable.” A little empathy can go a long way.

Then, Diamond recommends these four tactics:

1. Ask the right questions. “First, ask your boss to tell you her perception of your work,” Diamond says. “Then ask whether she thinks you’re worth more than you’re making. Explain that you know you’re underpaid relative to the market outside the company, but are you also making less than other people of similar rank inside the company?”

You should also ask what the company’s criteria are for giving bigger raises than the across-the-board 2.5%. “Seek out the standards they use,” says Diamond. If that information isn’t forthcoming, “focus on the company’s needs in the future. Ask, ‘What can I do for you going forward that would be worth the kind of raise I’m requesting?’ The answer commits your boss to a standard and gives you something to shoot for.” It might also be the basis for a performance bonus down the line.

2. Don’t make it personal. “Instead of saying, ‘I’m worth more than a 2.5% raise,’ talk about what the job is worth” — for example, how much your department contributes to revenues and profits. Says Diamond, “The conversation should center on the work, not on you. The less personal you make it, the easier it will be for your boss to justify a bigger raise to the people upstairs.”

3. Be prepared to think incrementally. It’s unlikely you’ll get a 20% raise all at once. “So try for a smaller amount now and more later on,” Diamond suggests. “The best negotiators don’t have a home-run mentality. They go for lots of little wins. Bunts and singles are what win ball games.”

4. Consider intangibles. Assuming the pay hike you’re offered (for now) is a small one, have a few other possibilities in mind. “Be ready to ask for something else besides money that matters to you,” Diamond says. Maybe it’s extra vacation time, a window office, a health club membership, or the chance to telecommute a couple of days a week — whatever would help close the pay gap, in your mind, and that would be a relatively easy “yes” for your boss.

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What can you do (besides quit) if you still hear “no”? “Start keeping a list of specific accomplishments — date, time, and task — and write down at least two or three items a week,” Diamond suggests. “In particular, be sure to include anything that saves the company money.” This way, when you ask again in six months or a year, “you’ll have a detailed record of your contributions, which is hard for any boss to say ‘no’ to.” He adds: “This is one of the surest ways to hear ‘yes,’ yet very few people do it.”

Good luck.

Talkback: If you’ve asked for a raise recently and gotten it, what worked for you? Leave a comment below.

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