Other than that, I've heard eating a pineapple plus it's core, walking, sex, bouncing on a ball or end of your bed/couch, raspberry leaf tea and a few more things but your body needs to be ready for any of these to work. Nipple stimulation is another but takes a lot of dedication if you look up how to do it!
Sex, walking, bouncing on a yoga ball. I've heard more horrible things about castor oil then good things.. my advice would be not to use it.
Roll on an exercise ball