How can you make your cervix dilate?
If you want to start contractions try playing with your nipples, you or your partner. Also climax works as well. Flights of stairs. I do not recommend Castor oil. it is harmful and you wont get the result that you are wanting
Don't know for sure about actually dilating, but to start up labor [get it going faster] walking "A LOT" WORKS WONDERS!!