Watch the Picking Hand Posture online guitar lesson by Brad Carlton from Guitar Lab: Solid Strumming
This lesson covers many facets of the picking hand. The first principle is how to hold the pick. I will demonstrate the principle of relaxation by addressing the muscles of the forearm, wrist, hand, and fingers. Economy of motion is critical for precision, so you will see in the video how to minimize your effort while maintaining accuracy. I will address the following techniques in this video: all four positions of the wrist and fingers, all three pick angles, free strokes, rest strokes, palm mute, palm slap, choke, down strokes, up strokes, and accents.
You will learn how to view strumming as a series of rest strokes which allows you to control the dynamics and tone of each string(voice) of a chord. You will clearly see in the video how dynamics are controlled with the thumb and index finger. To play softer, you hold the pick loosely. To play louder, you simply squeeze the pick harder. This technique is especially effective in creating accents in your strumming.