Part of it too is the, um, perkiness, as far as going Peri or double incision. You can get away with a larger cup size for peri with less saggy man-boobs.
As a straight guy, I usually do a visual guess. AA is too small to see. A you can see with a tight shirt, but not too well with a baggy one. B is a comfortable handful (ok that's not visual, but whatever), C is an overflowing handful, etc. D is pretty big. I can't see from what I see of your build that you'd be a D unless you're a bit disproportionate.
If you can handle it, the easiest way to figure this out is just to go to a department store, grab a bunch that you think might be close and try 'em on. Not sports bras, but regular ones. Then just walk out without buying anything. At least you'll have your size. Size varies somewhat within brands, but it'll be close enough to tell the surgeon. Otherwise, measuring for yourself is going to get confusing. People do this stuff professionally - fit measurements to bra sizes.
Or, steal one of your mother's for a minute and check the cup size. Guesstimate based on that. Unless your mother and you are totally different. The band size obviously won't matter if you're different there.
Dennis
