Baby ready, but not cervix

So my doctor checked me down there.... Baby is head down, healthly and all that good stuff... My doctor said baby is reaaaaaady to come out. Her head is really down there, and I'm around 30%-50% effeced but my cervix is open on the outside (whatever that means) but 1/2-1cm dilated... She said I can go home and start doing nipple stimulation. She didn't give me a membrane sweep today, but she gave me a thero cervical check.... My question is what can I do to open up my cervix besides sex and stimulation...... And how many primrose oils should I start taking now!!! Thanks.