Know these answers before having surgery
Permamently (or even semi permanently) altering your appearance through cosmetic surgery is a huge decision. Once you go ahead with it, you can never return to your natural self (we've seen even so-called "non-permanent" procedures such as collagen injections have lasting effects on one's looks).
So it's not a decision you should make lightly or on a whim. Add to this the fact that the procedure will likely make a significant dent in your savings, so you want to be sure spending that money is what you truly want and is for the right reasons. Also to take into account is that any procedure has its risks.
Of course, these are things you can and should discuss with your plastic surgeon, but it's a good idea to put some thought into them on your own first. Consider some scary examples of celebs who've had a lot of work done (think Heidi from The Hills) and who probably should've thought a bit more before undergoing all their procedures.
Why do you want this cosmetic procedure?
Consider the area or body part you want to alter. What about it do you dislike, and why? Have you tried other methods of dealing with or treating this area before resorting to an elective surgery? Do you want to undergo this procedure for yourself, or to please others? If it's to please your boyfriend or husband, consider hard whether this is what will make you happy and comfortable in your own skin. Remember, people are fickle, and the only person you have control over is yourself.
What do you think changing this part of you will result in?
It's best to have realistic expectations. If you expect the outcome of the surgery to completely turn your life around and everything will be pure joy and happiness, we need to point out this will likely not be the case. Do you believe the results will make you feel more confident? Remember that confidence comes not only from appearance, so you may actually have more work to do in terms of your frame of mind. A new nose, for example, will not instantly translate into a bold new you.
Consider potential negative outcomes
Every procedure carries risks, no matter how slim. Learn about those risks, and think about whether the possibility of something going wrong is worth having the procedure done at all. Consider how you'd feel if you ended up being one of those unlucky few.