Pop off the hook and place it on a flag or a tee at the far end of your practice line. Hold the reel so that it will spin freely as you walk to your starting point, usually by placing a thumbtip and fingertip in each side of the hole. Place the reel on the green, insert a tee through the hole, and give a slight turn to tighten so you have a straight line flush on the ground that you can putt straight down.
Place the hook on the flag and walk to the first ball, holding the reel in your fingertips. The line spins off easily. Hold the reel tightly to maintain the set length of line. Just walk around the arc to the other ball and see which is closer. Then, simply insert the specialized Rewinder through the hole, ensure the line is in the guide slot, and give the reel a spin. It will rewind very quickly and neatly. Then pop the hook back onto the spool, keeping the larger end facing opposite to the winding so that the hook is anchored. This ensures the hook will pop off easily next time and not slide around.
Replacing the hook as pictured anchors it with the line. When replaced "backwards" like this, a slight push on the nub at the other end from the string will pop off the hook.
Insert the Rewinder through the hole in the Greenie String. Hold it with the Guide Slot up and the line coming off the top of the reel. Lay the line into the slot. Give the reel a spin! Fun and done.