When I don't totally feel like drawing but know I should, I randomly select a category from http://artists.pixelovely.com/ and I set it on 1-2 hour class mode. this warms up my mind and my hands to draw by sending me through some 30 second gestures, then some one minute gestures, and then sets 5 and 11 minute figure drawings. I never usually go farther than the 5 minute on expressions because by the one minute mark I'm already trying to find things to fix or in the case of simple poses, I start to shade. Obviously my 30 second gestures look like total crap but gestures are hard on digital. There is not the freeness of gesturing on an 12x18 sketch pad as I did in art school.

But yeah...'s how I warm up some days.