|Bow exercises are great. Here is a good one to work on flexibility and finger independence in your right hand. (You can try it left-handed as well!)
Hold your bow vertically using the correct bow-hold, and slowly and carefully crawl up the bow stick like a spider. Try to maintain a correct bow-hold position as far as it is possible, making sure that the thumb remains on opposite the fingers. Stop when you get half way up the stick, and then crawl back down to the frog again.
Once you have successfully spider-crawled your way back to the end of the bow, reverse and head toward the tip again. When you get half way pu the stick reverse again and come back down. A third trip half way up and back will complete your exercise for the day.
Always be sure to wipe your bow off before you put the bow away!
If you do this exercise daily for three weeks or so you should notice a difference in your ability to handle the bow with your fingers. Strength, flexibility and finger-independence are all critically important in the proper handling of the bow. This exercise should help you in all three areas.