Do you have a trustworthy midwife who is looking after you daily? Most midwives have "secret" remedies to start labour, but you should not experiment on your own. I remember being threatened with induction and my midwife was going to give me a "Rizinus-Cocktail" (no idea what that might be in English), but I didnt' need it in the end.
I think what helped me was relaxing, admitting that I was s*** scared of giving birth, pep-talking to me and my baby and an aromatherapy oil that helped me to let go (I know that sounds silly myself, but I also know that you get VERY desperate...).
Clean the windows, then have a hot bath, a glass of red wine, sex afterwards and hopefully your little one will be on his/her way soon!