Put your money in a savings account, and make plans to put X amount of your paycheck in the account EACH paycheck, and even squirrel away a little bit here and there. This way you're not tempted to spend your money, and you can get a concrete idea of how much you have and how much more you need.
I would go against the gift cards. While creative, they're too much of a risk. If you lose it or if it gets stolen, it isn't insured and you lose your money.
Try doing odd jobs and just get the word out about what you can do (computers, handy work, lawn care, etc) through parents, friends, neighbors, etc.