How to induce labor naturally?

Lorna • Queer/Bisexual 16 yr old who likes to help people. Qotm: "throw me to the wolves and i will return leading the pack"
My friend from primary school is having a baby and she is 5 days overdue. I wanted to give her some useful tips on how to help her baby come. 
So here i am asking the lovely ladies (gentlemen and whatever you identify as) of Glow. 
Do you know any ones that help bring on labor? 
Thanks :)))