Great advice @Doulamommy. ;).
If your body is ready for labor, a warm bath can help prep your tissues and even relax your cervix so it dilates faster. For some women however (I think about 15%), warm water can slow early labor so the bath is a bit of a gamble.
Ive heard sex(orgasm and sperm cause contraction) walking, raspberry tea, light lifting (less than 10 pounds, like light weights using core muscles)
And there's a lot of other ways you can look up on google
Your baby will come when your body is ready. All the old wives tales about eating fresh pineapple, walking, eating spicy things, red raspberry leaf tea are just all myths. Since 38 weeks, I ate 2 whole pineapples in a week, had sex 3 times a day, walked a lot (from one end of the college campus to the other multiple times a day), drank red raspberry leaf tea (which I was told actually helps tone the uterus so you don't hemorrhage, the contractions aren't strong enough to kick start labor). Your body will know when it's ready. Just get as much rest as you can now because once baby comes, you won't get much!