Native,
For the voice thing, I find it best to pick someone's voice that you find powerful, masculine, and appealing to have (Alan Rickman like Ross said, George Clooney, etc) and trying to imitate their voice. I have some trouble with voice too sometimes, and I find it helpful to just focus on slowing down my voice and enunciating everything I say clearly.
As for fashion, I always try to be just a little bit over-dressed for the occasion. For example, at school I'm almost always wearing nice button downs with a nice-fitting pair of jeans and good-looking shoes/boots. I've been getting compliments from a lot of girls in my social circle on how I dress (and even some guys too). You don't want to go too overboard and look try-hard, but overdressing a little bit can't hurt. It also depends on the style and image you are looking for, but there's a lot of ways you can look stylish and fashionable.
V,
1. Move down a shirt size. This does WONDERS. It really is like a cheat code. You go from a scrawny guy to buff with one or two size changes. When I did this, people told me that I'm looking good and got big, but in reality I hadn't gone to the gym in weeks. This plus correct posture is huge.
2. Find an style that you want to imitate. I'm a big vampire diaries person. So I've stolen a lot of my style from them. Dark jeans, dark blue, grey, black, dark red shirts. I'm a pale white guy, so it looks good on me and it isn't too much of a stretch.
1. Agree 100%. Most guys are always wearing sizes way too big when they could easily go down a size or two. Not just to accentuate your body, which is always huge, but the whole baggy shirts and pants thing doesn't look good at all in general. Even with pants, most guys could go down a size or wear a belt. The sagging pants halfway down the ass so you can see half of the boxers (I'm exaggerating a little, but seriously what are those guys thinking?!?) looks terrible and I don't think it would be bringing any high-quality girls.
2. Me too. I know that some of the characters have been wearing long sleeve shirts with a button placket halfway down the chest (but not a legit button down). Don't know what they're called, but I like those. Seen anything or gotten anything like that anywhere?
A kind of general question I have, but what fundamental specifically is the most powerful/beneficial/important to have? Obviously all of them are important and good to have, but which one should I (or anyone else) try focusing more time on specifically to improve? Basically something that would give me a big boost in attractiveness/sexiness and is a must-have. I've gotten fashion down pretty well and am still trying to improve, and I'm trying to think of what I should target next.
-Pato
. Don't get too caught up in categorizing things - the point is, working on fashion will increase attractiveness. 
