A doctor uses a a special tool to break your water. Caution: do not do this yourself, you could harm yourself.
Let nature take its course, if you break your waters too early at home, you could have a dry birth, and you take the risk of getting an infection; which can harm the unborn baby. This is not the right place to learn about this, talk to your OB/GYN. The doctor is the one who knows when its the right time.