I think for me, it was all in the mind. Tell yourself you're going to do it and don't allow yourself to cave. If you think you can then you can-it you think you can't then you can't. That always gets me motivated.
Another thing, (if you're not ready this week), is I cut down to small portions and then to just fruits/veggies and finally to just juice for dinner, then a day of only juice before I did the fast. That really got me ready and I know for me, I would not have made it this far (day 5) if I hadn't done that. Lots of people just jump right in though and are just fine. It probably has a lot to do with being close to that time of the month. Your stomach must kill though. When I was doing just fruit/veg with juice for dinner, one day I caved and had rice and my stomach hated me all day the next day. That's something that keeps me from even considering breaking wrong now--I remember how much that hurt.
Good luck. I know you can do it if you put your mind to it. We are all here to support you.