Irene - you can pick up a lot of suggestions for wrist exercises if you google "wrist exercises". You could start out with a light hand held weight and build up from there.
I have a Dyna-Flex Power Ball I bought a few years back that is really helpful, but it's not easy to learn to use. It takes quite a bit of strength to control it. You could build up first with a light weight and then if you wanted to go on, you could get a Power Ball. It works the hand, wrist, and up the arm. I probably bought mine from Overstock or Amazon. My instructions list www.dynaflex-intl.com.
The Power Ball was hard for me to catch onto. I messed around with it a lot before I learned how to get it going, and then its hard to control. It works for me but it may not work for you. You might have better luck with light hand held weights and stretch bands.
Mary Davis Nowell. Based close to Fort Worth. Shopping Interstate 20 east and west, Interstate 35 north and south.