I've tried all and still nothing at 39 weeks, your body will just do it when it's ready. one thing I've been researching though is getting your membranes stripped/swept. I'm gonna ask my doc to do mine in a couple days! I've read it sends people into labor that night or the next day

Exercise, nipple stimulation and spicy food

bouncing on a yoga ball, sex, or tons of walking. Although I can say I did all 3 and wasn't even dilated that much when I went into labor, they do help though, for some more than others.

Sex!!