No way to change the shape of a muscle. It only gets bigger or smaller. BUT, there are tricks. If you look at different bodybuilders doing front biceps poses you'll notice that they all point their hands in different direction. Sometimes their fists face their shoulders, sometimes they face forward. That's because the way you face your hands changes the gap between your biceps and your elbow, because of where the tendon connects. If you do a little posing in the mirror you'll be able to find the balance between making the best biceps peak possible and keeping your gap as small as possible by twisting your fist back and forth while you pose.
Current PRs at 242, raw w/ wraps- 525, 355, 605, 1485
Roboro tui, perimo vester adversarius
(Build yourself, destroy your enemy)