For me, it's a combination of visualization and planning. I plan out my food in advance as well as my exercise. Nothing stands in my way. I have chronic daily migraines and I still workout, so if I can do it, anyone can.
I also agree that weight training has to be incorporated somehow, along with moving every day. Finally, the more I visit 3fatchicks, the more focused I am. Oh, I forgot: don't look at any long term goals. I just focus on 10 lbs. at a time.