To be serious (and not a sarcastic asshole as I was earlier), as a student who pretty much did the same thing as y'all are looking to do, the best advice that anyone on here can give you is to lurk. Read pages of WAYWT. Find brands that you like and research the hell out of them. Figure out where you're willing to make quantity vs. quality meet (everyone here will tell you to buy expensive things because they last -- students don't always have that much time to do so).
My personal style has shot all over the place through the course of college. Freshman and sophomore years, I was obsessed with the SF "look." I wore APCs, plain tees or basic OCBDs, a TOJ leather or other simple jacket, and either boots or chucks (GATs weren't quite staples yet, I don't think). I picked up the denim for full price and then worked my ass off to find the rest. At times, you have to go against the forum recommendations (and, in doing so, I found a pair of Fryes that I really liked, that were cheap, and have really held up for three years with heavy wear).
Pay more attention to fit than anything else. The odds are that your clothes are too big. Make nice with a tailor. Look into Brooks Brothers slim and extra slim fits (they've worked really well for me) as well as other brands on clearance/sale. Try shit on before you buy it and be totally satisfied with a purchase before you take the tags off (I have a rule of leaving it in my closet for at least a week before I take the tags off).
But realize that there are NO hard and fast rules (outside of fit, I think). The forum opinion changes as readily as it gains and loses members. If you're not comfortable in raw denim/tshirt/GATs, then find other clothes that are of decent quality and play around. You'll make mistakes. Eventually, if you stick with it, you'll figure out what you like.
Finally, if you're dressing well to impress girls, stop. They don't care. Don't look like a slob and you'll get compliments. Compliments build confidence. Confidence wins people over.
