Holding your guitar pick incorrectly will slow down your improvement. Holding the pick too tight can cause cramping and holding it too loose can cause the pick to move out of position while you are playing or you may even drop it.
Some people prefer thinner picks which may be better for strumming certain styles while thicker picks are good for bass or handling rhythm and leads on an electric guitar. There are also medium gauge plectrums that fall somewhere in between. Initially it is a good to buy a variety and experiment with what feels right for you.
Once you’ve got your picks, make sure your strumming hand is relaxed. Gently put your index finger and thumb together then close your other three fingers toward your palm.
Place the pick in between the thumb and the outer edge of the index finger, so that the index finger is pointing down toward the tip of the pick without poking out beyond it.
Hold the pick firmly, but not too tightly. Try and keep a good amount of thumb on top of the pick to keep it from moving. If you are strumming, you’ll want to have a larger portion of the pick exposed. Less exposed pick surface can give you better accuracy to hit single notes.