I pace myself. Having a plan puts my mind at ease.
I once had to juggle 8 huge design jobs at once...however my mind just kept reverting to minecraft, which killed more time which left me more stressed by the end of the night.
I finally sat down and just wrote out an agenda.
"This is when i'm going to make this flash app, and i'm going to have done by here. This is when i'm going to start this photoshoot, and i'm gonna finish it here and fast track that vodka campaign.."
After just filling it out, my mind was at ease. I even managed to write in some minecraft time before starting all that work.