Ok, but seriously....

With the exception of that one time at Home Depot last summer...

I make sure I'm the only one in the bathroom, discreetly undo my zipper just enough to pull out the bare minimum required to perform the task at hand, and relieve myself.

Oh- the one strange thing I WILL do is wipe the drip off the end of my dick with toilet paper if I'm at a toilet in a stall. If at a urinal, I try to squeeze and shake it dry as quickly and discreetly as possible.