I have an old aluminum tennis racquet that I'm looking to replace after having broke its strings. I know neither my hand's grip size nor the racquet's grip size, but I do know that the racquet is the right size for my hand. I looked up methods for measuring my hand's grip size, but I didn't find them to work well for me. However, if I can measure my old racquet, I'll be all set for getting a new one.
How can I measure the racquet grip size?