Anywhere from 20 mins to a couple of hours. It depends on what I'm doing with the layout. Sewing, inking, stamping, painting...Some things take some time.
I think I have the same answer as most with 30 min to a couple of hours. Couple of hours if I get stuck and what I was thinking wasn't working. Really the longest is collecting papers. I think that takes me at least 45 min or a few hours (after I change my mind a few times). Thankfully with some great sketches and challenges from here it gets a bit easier for me! This past Sat sketch was great and I got through it really quick.