First, I decide what I want to do (with all my UFO's, surely one will interest me).
Second, I set a timer for 1 hour. I spend this time sorting things out - re-reading the pattern, checking what's cut and what needs to be, etc.
Third, I set the time for 1 hour (again). By now, my mind is clear and I usually know why I started the project in the first place. I can start where I left off.
When the timer goes off the second time, I'm in the swing of things and can't stop!