How do I let water out of my pool if it is to full from the rain?

Pull the plug out of the bottom. Kidding.

Put the male end of a garden hose in the pool about a foot down from the surface. Attach it briefly to the faucet and basically fill the hose. Generally, if you can disconnect it fast enough, you will create a siphon as long as the other end of the hose is below the pool end water should flow out using gravity as the pump.

Mouth siphoning is also possible once you have a filled hose. However, certain garden hose materials your not supposed to drink out of and your not supposed to drink pool water either. With mouth siphoning you suck on the end of the hose to start a flow and put it on the ground quickly. If your good, you don't get any in your mouth.

I always "backwash" mine , if ou have a pump. The pump does the work for you and it cleans the sand filter.