Heroically coined by morning jock Elliot Segal on DC101 as a t-shirt design. it means absolutely nothing except when you say it, you gotta say it like white trash. it also makes a great insult when you can't think of anything to say.
Say i was going to the White House but couldn't figure out which tux I'd want to wear. Then i'd probably just put on my "Smell My Face" t-shirt and some jeans i wore the day before
In the old days when we were young we used to use the phrase. Smell my fingers which in that time would prove that you made it to second base with a girl. Now a days they use smell my face to prove you made it to third base. This in a nutshell means that the male had oral sex with the female.
I had a great time with my girlfriend last nite Jim here Smell my Face!