How can I make HD YouTube videos!?

Well, actually, I want to re-upload the Vanessa Hudgen Kohl's candy girl video, but I want to upload it in HD. (720p). I NEED EASY WAYS TO DO THIS!!!!!!!!! I have CAMTASIA STUDIO 7. oh, and dont give me the &fmt=18 thing, it said to have stop working after they got the 240p - 1080p. AND HOW DO I RE-UPLOAD THE VIDEO!?