Why You Need a Thumb Rectangle
Beginning guitar players have a lot to think about. A thumb rectangle helps you get your left-hand thumb in the right place every time without having to think about it. It also keeps your thumb in the same place even when your changing between different fingers, making your playing more efficient.
So here is how to add a thumb rectangle to your guitar. Remember, function is much more important than aesthetics. As we go along you will notice that I am no Martha Steward; you needn’t be either.
What you need
You can use just about any kind of tape. For this example, I used fluorescent orange duct tape for higher contrast. Keep in mind, you will eventually want to take the tape off. You can use rubbing alcohol to remove any leftover adhesive without doing any damage to the guitar.
What to do
Make sure to have your thumb in the thumb rectangle whenever you practice. Over time, proper hand position will become a habit and you can remove the tapes.