There are many ways to induce labor medically. Doctors may give medicines, hormones or a medical procedure to soften the cervix and to bring out contractions.
Unless you were asked to bed rest, you should be moving and exercising throughout pregnancy. Gentle exercises like walking, sitting on the ball, swimming can help relax the body.
Sex during pregnancy is generally safe unless you are flagged high risk for pre-term labor or placenta problem that your doctor must have discussed with you.
Human semen contains hormones called Prostaglandins, which can dilute and soften the cervix in preparation of labor. Orgasm also releases Oxytocin, which helps the uterus to contract.
Practice some relaxation techniques like listening to positive affirmations, meditation or even sleep can help prepare your body for the upcoming labor.