The appropriate wingspan question has been discussed before, see
http://www.chronicles-network.com/fo...f-a-human.html.
The question of shirts, well, that's a new one. Are we talking business shirts here? You would probably opt for something that goes on backwards, like the type HardScienceFan wears (just joking Ben
) so you just put your arms in and tie it up at the back. Otherwise something skimpy and in leather. If you've got wings I doubt you need to dress business/casual.