Asking for a raise can be a very risky proposition if it's not planned out correctly. As a general rule, employers believe that they are paying their employees fair market value. Therefore, the odds of getting more money are usually against you. The best approach is to establish credibility with your immediate Supervisor by consistently exceeding expectations. You're in a much better bargaining position when you have a history behind you. So, timing is critical. You need to spend the time necessary to develop a reputation as a results-driven and highly valued employee. This approach can take six months or several years because you need to have the opportunity to show what you can do. If the opportunity doesn't present itself, you need to take on increased responsibility to demonstrate your skills, work ethic and value to the organization. Once you have established a reputation of consistently adding value, your odds of negotiating a pay raise is much improved.
The approach is also critical. When asking for a raise, you must never demand or insist; diplomacy is crucial. It is always good to begin by reinforcing your commitment to your Supervisor and to your employer, while also thanking the company for the opportunity to acquire new skills and to demonstrate your abilities. You can then talk about the financial pressure you are facing including inflation, tax increases, tuition increases, unanticipated expenses (e.g. home improvements), and other factors. This approach indicates that your reasons are due to events that have simply overwhelmed you, and your reason is not based upon the greed factor, but the survival factor.
When you close the discussion, make it clear that you will remain a loyal and committed employee even if the answer is no, but that you would appreciate any consideration. If the answer is no, it is a clear indication that your company many simply lack an appreciation of your efforts. This is good information to have, since the culture of your company is unlikely to change in the near future, and you can now exercise your options. If the answer is yes, you have won. However, the company will now expect more from you and you will have to deliver. Finally, never discuss your plans to ask for a raise or the final outcome with anyone, and I mean anyone. Companies do not want to be in a position where your success will lead to a rush from other employees looking for pay increases.