Assuming I have 20-30 minutes for sound check (common except for festivals):
I tend to do monitors first with mains off, then mains, then back to monitors for fine tuning, EQ, then back to mains, then maybe a final pass of mons if anyone needs something different... There are valid arguments for either approach, I've just settled on that workflow. I tend to go back and forth a lot, I ask the band constantly how it sounds for them, and what can I do to make it better.
Fist pass is usually 'what goes in each monitor', and general levels. 2nd pass is EQ.
Then I ask the band to play a few songs show varying dynamics and set Mains, EQ, comps,....
Final pass I have the band play their opening song (first 20 seconds or so), and maybe repeat, for final adjustments in mons and mains... The save the scene. This helps make everything cooking for the first song when the act walks on stage.
My job is a whole lot easier (and faster) with iPad remote control.