You do NOT have to do it all at once.
Pick one little thing, 2 less chips, walk one block, make your bed, whatever.
It's a life style! It is much easier to do small things, in small doses. Celebrate, the little things, the big ones will follow.
So, tomorrow, one little food thing! One less chip, one less cookie, whatever!
Then, pick a non scale, food, exercise, thing that you would like to tackle. Dump the trash, make the bed, wash a window, file your mail, call your Mom, paint you nails, whatever.
Celebrate the positive!
The more you celebrate the small positive things, the more the BIG negative things will fade away.
It takes time. Old habits die hard. I know!