Don't Do It!
I seem to be unusual among men my age--at least, among men my age that I know--in that I rarely button this button if I'm not wearing a tie. My stepdad told me once when I was a kid that it made me look nerdy, which has stuck with me ever since.
BG39:
See, now my uncle had told me the same thing. I button it just because I don't endeavour to be cool.
Button the collar! Be free to button up!