What Do You Want?:
The first thing you need to do is define exactly what you want. If you don't ask for something specific, it will not be offered to you. "I want a raise" is a good start. 

I'd Like To Thank The Little People:
If you mention the "R word" to your boss, prepare for a melodramatic performance. Your boss will immediately adopt a sad puppy-dog look and give you a woeful tale of hard times within the company. As charming and friendly as she may be, it is your boss' job to maintain the budget's bottom line. But don't worry, your boss' little aria is only the first act, we have a long time to go before the fat lady sings.

You Work For Me?:
It may sound silly, but make sure your boss knows what you do and how well you do it. A biweekly memo or email outlining your outstanding accomplishments and wily outfoxing of the competition will set you apart from the pack and garner you attention.

Research, Research, Research: 
If you suspect that you are tragically underpaid given your title and industry, hit the library or the Internet to find out what your peers are making. If you're afraid of librarians or don't know how to use the Internet then read the trade journals and classifieds or call a headhunter or professional organization and ask them. Pretend you're writing an article, and are doing research. They'll have the most up to date and detailed information.

What's On The Back Of Your Baseball Card?:
Next, consider the ways in which you have manifestly and tangibly contributed to the health and well-being of your firm. How is your performance above-average? Have you cut manufacturing costs 10%? Have you reorganized the typing pool to maximize output without increasing the budget? Have you consistently outperformed your sales quotas for the last three quarters? Have you taken on more responsibilities than your co-workers without any adjustment in salary? Any example where you can show in hard numbers what you have accomplished will work in your favor.

Ready? Aim. . . :
Take the time to write down exactly what you're asking for. Is it a 20% increase in salary? Ask for 25% to give yourself room to negotiate down. Be prepared to give in on some points. Do you covet extra vacation time? Exactly how much (and while you're at it, how will you cover your responsibilities)? If your company has recently downsized and you find yourself doing the work of three people, mention this too. If your boss needs to relay your request to a higher-up, this cheat-sheet will help her make your case.

How Do You Get To Carnegie Hall?: 
Practice. Ask a friend to do a rehearsal with you. Anticipate what your boss' concerns might be and be ready to address them. 

Have You Seen This Photo Of My 45 Kids?: 
One last note, forget pleading poverty. No one ever got a raise by claiming hardship. The big boss will just as quickly suggest you default on your car loan and take the bus as give you a raise. Unless you are the "teacher's pet", the only way you're going to get this raise is via your professional accomplishments.