How to decide between two girls you really like?

Well there are these two girls I really like.One's name is Diana and the other's name is Taylor.They're both in the same homeroom and one of them is in one of my classes.I have liked Diana since the beginning of the year and I have liked Taylor since last year.They're both nice and Taylor asked me out last year and I said yes.But she got moved to a different class before we got a chance to date.And Taylor already knows I like her and I think Diana does too.And also Diana is Skinny and Taylor has a flabby stomach but her sides are skinny.I really want to ask one of them out but I don't know which one to ask out?

Thom33 long time no see.. that's cool talk to them both any trouble with that one kid Kessler or whatever the name?