We make sure that our backline sounds good first, and that the drums are tuned, this is done in the practice room. Then small adjustments are made for the room we're in, but it's usually very minor.
We play some music first to make sure the PA sounds alright in the room, adjust the sub...
We do vocals first, the rest of the band listen to me line checking, then the kick, snare and toms to get a level on the whole kit (we don't usually use an overhead for the cymbals in pubs, they're loud enough)
We play so regularly that the guitarists know what sort of levels they need to be at on their amps anyway, so we then play two songs with varying dynamics, so we can get a balanced mix with either me or the guitarist out front listening to levels.
We mic the guitars only if the room is big or there's something directly in the way of the crowd, there are a few gigs where we're "enclosed", so we put everything though the PA and point a speaker in their direction.
Then, after aaallll that, I bring the foldback mix up and we play.