You’ll need: Styrofoam balls, mixture of sizes; natural and colored jute or cotton string, hot glue and hot glue gun, straight pin. 1. Make a small knot at the start of the jute or string. Place a dot ...

Forbes contributors publish independent expert analyses and insights. Tim Newcomb covers tennis gear/business, stadiums and shoe tech. So much is made about the technology of tennis rackets. But don't ...