Don't worry, Sora has girly eyelashes, it'll be easy!
lol but seriously, all you really gotta do it try to get your hair/wig done right. As for the body, just do your best on the outfit. If you've got a noticeable chest, try covering it up with the shirt and jacket. Also try making the shirt a little baggy, this makes it look more boyish and won't show of your curves (this would be easier to do for KH2 sora than KH1 sora outfit)