I did mine myself...
The problem with free floating a 10/22 is that it only has one mounting screw. It's a good idea to bed the action and/or have one support point at the muzzle end of the stock - which is what I did.
If you are using a bull barrel, get yourself a 1 inch diameter dowel and wrap sandpaper around it, then sand the barrel channel out. Check periodically to see if it free floats. Once it does, you can decide what to do to support the weight of the barrel. On mine, I simply installed a piece of rubber inder the barrel close to the end of the stock. When the action is screwed down, it compresses the rubber slightly leaving a pretty constant tension on the barrel and reduces vibration.