Guy-1: Hey, I just won that hard sporting event!
Guy-2: Neat, that’s something to place a feather in your cap for!
Guy-1: Okay, what's that mean?
Guy-2: umm.. I don't know, let me look it up on urban dictionary. By the way, does that guy over there have his earring on the right ear?
Guy-1: why.. yes, yes he does! He must be a homosexual, for a straight male would wear it on the left.
19th century use:
Gentleman-1: Good morrow, friend, did you see that rousing game of stick ball?
Gentleman-2: Why yes, you sure did show those men whose the better stick-player. That's something to put a feather in your cap for.
Gentleman-1: Why yes, yes it is. But I better place it on the left side, as I am not a homosexual.
History-slug: Remember kids, always place the feather on the side that fits you best! Homosexuals and females on the right, straight males and lesbians on the left!