Abstinence......Hee hee, yeah right, like is there anyone on here that can preach that?! If there is someone, I take my hat off to you!!!! Anyway, yeah like everyone else said, no matter what you do to prevent it, if you have sex you also have to understand that you could also be doing something that could forever change your life. And just like there is no 100% prevention against pregnancy, there is also no 100% prevention against stds...Not to scare anyone, but the aids virus is a hell of a lot smaller than a sperm (think sperm= football field and still sometimes gets through the condom, aids virus= football) it is scary, so be as safe as possible, use a condom, a diaphragm, spermicide foam, and b/c!!! Hee hee, j/k.
But seriously, be careful!!!!