Swallow. I'm in a long-term relationship - intimacy 12 years, married 9, so we've enchanged pretty much all the body fluids. I think a guy likes it when his cum is swallowed, but obviously there are lots of other variations - with plenty of great examples here at TFP.
Swallowing is more practical, tho' the texture is somewhat like raw egg whites. It's fun to swallow and kiss my man. And it's a great way to share.
Edited cuz I can't freakin' spell!