Hi Sally! Welcome to ATP.
It's a shame you have to give up your beautiful plants. I assume they are planted in your yard, not in pots. You don't say where you are located. And you also don't say if these are herbaceous peonies or tree peonies.
It's probably not a job for someone with bad knees and a tired back because you are going to have to lift the entire plant out of the ground and divide it without causing too much damage to the roots. Carefully dig around the entire plant and lift it out of the ground. Rinse all the dirt off so you can see what you have and start separating. Decide where the crowns are then use a sharp knife to cut the roots apart.
If you have a locally owned nursery, chances are they would be interested in your plants and also be willing to come dig them up. If there is a peony society near you, they would be a good resource. Below is the link to the Peonie Forum in ATP. They seem to be very active:
Best of luck.