The worst part of many people's golf game is putting. If that's your problem, you've probably bought umpteen putters with the hope that you'll finally find one that works for you. But, alas, they have all found their way into the closet, and you're still looking for the one that will help you reduce your score. Making your own putter may be the answer and it is really easy to do.
Trim the shaft. Typically, shafts come in one length so most likely you will have to cut it to fit. If it is made of steel, simply mark where you want the cut and then cut it using a hacksaw. If it is a graphite shaft, first wrap it with a couple of thicknesses of tape, then mark where you want to cut it and use the hacksaw to finish the job.
Prepare the clubhead and the shaft. The tip of the shaft should fit tightly into the hosel, or connector, of the clubhead; but first, you must roughen up the tip and the inside of the hosel with the sandpaper. It's a bit more difficult if the shaft is made of graphite because you first must strip away the polyurethane coating from the tip with a belt sander then use the sandpaper to roughen up the tip of the shaft.
Apply epoxy to the tip of the shaft and to the inside of the hosel, then marry the two. If you're working with a graphite shaft, the tip may not fit into the hosel. In that case, do not try to re-sand the shaft but rather increase the inside dimensions of the hosel by sanding it until the shaft fits snugly inside. Then apply the epoxy and continue with the installation. Once the shaft is inside the hosel, twist the shaft back and forth to make sure the glue is entirely covering both surfaces. Finally, make sure that the shaft is all the way into the hosel by rapping the butt of the shaft against a hard surface while holding the clubhead.
Check to see how far the grip will extend down the shaft, then wrap the shaft with the double-sided tape in a serpentine fashion to where the grip will be installed. Using the grip solvent, totally soak the tape. Then pour a bit of the solvent into the grip and make sure that it covers all the inside of the grip. Gently slide the grip onto the shaft, making sure that it is on all the way. The grip solvent needs about a half hour to dry, so you will have plenty of time to make last-minute adjustments.