I just set a goal, even if that goal is to go to the gym 2 or 3 times a week ( 5 or 6 in my case! ). I know I will feel dissappointed if I didn't do it, so I just GO.
It's become more habit now, and there are days I'm not sure I really feel like going in, but I do it anyway. I know that if I don't, it may be easier the next time to just not go. Also, I really do feel better once I am actually there, and feel better about myself afterwards.
I also don't weigh myself... well, not often anyway. I have taken measurements, and do that every couple of weeks or so. I just don't want to be consumed with the amount of weight.
My clothes fit a little better, and I just feel better all around. That's enough for me.