I was always told sex, hat bath, and or hot tub. The hot water helps loosen everything.
^_^ good luck!.. well the best I heard is sex helps because the sperm has I forgot what in it that can start your contractions.. some fresh pineapple helps! If you walk a lot and go up stairs it can help open your cervix and hips more..(: my dr has allowed me n my hubby to start trying natural induction yourself and told us that's what could help