Yeah, that depends on the kind of girl you're trying to get. Dress and groom yourself nicely, that's about it. Shave. If you have long hair and it's not really nice long hair, cut it. Dressing nicely doesn't mean wear Armani, although that helps tremendously. Get an Armani suit and you'll be beating them off with a stick. But unless you have 1000 dollars to blow on a suit, wear something that looks nice on you.
Baggy shit makes people look like homeless people...it's shit, it's ugly, and it makes you look cheap. Stay away from American casual fashion.
You also should maybe re-think the kind of girls you're going for. You have to remember that many 20-something American girls are clingy, selfish, competitive, petty, and insecure little cunts who want lavish praise showered on them all the time and the entire world to revolve around them. Find someone you can connect with and you'll discover that none of this will matter anymore. You can wear whatever you want and be yourself. Out of all the girls you know, are there any that you can really connect with? If not, don't even try...you'll just regret it because there are so many Jewish princesses out there these days.
If you just wanna get laid, then go fuck a hooker. That's what they're there for. In fact, save your money, buy a ticket to Amsterdam and get high and laid for a week, all legally, and then come back and tell everyone you went to Amsterdam and got high and laid for an entire week.
Or you could just name-drop some places you've never been to and just pretend like you have. Make sure you study up on it. Just use a lot of nice adjectives and formulate a story. Girls love Europe, even though they know absolutely nothing about it, even if they've been there.
On a serious note, just be yourself man. If you can't connect on a higher level with anyone in your social group, then stop fishing in that pond. That doesn't mean you have to stop being friends, but there's nothing wrong with finding new friends. In fact, if your friends are keeping you in this vicious circle, why even bother with them?