Adjust the guitar strap so that the guitar is at a comfortable height. The angle of the wrist and forearm depends upon the height of the guitar.
Hold the guitar pick between the thumb and the index finger so that only the tip of the pick is exposed. Most guitar players strike the strings with the tip but other players, such as Pat Methany, use the rounded edge of the pick to achieve a more mellow tone.
Anchor your forearm on the guitar body so that your hand can reach all six strings easily.
Rest the heel of the palm on the strings near the bridge of the guitar. The heel of the palm helps to balance the picking hand and it also serves to mute unwanted overtones as you play the strings. Place the tip of the little finger on the guitar for extra balance and support.
Strike the strings at different angles to achieve different effects and tones. Holding the pick parallel to the strings produces the clearest tone. Slicing the strings at an angle produces a less clear tone. Where you strike the strings also makes a difference. Striking the strings near the bridge produces a treble tone. Playing nearer the neck produces the most mellow tone.
Practice alternate picking using your forearm, index finger and thumb, and wrist control. Most guitarists rely on wrist movement for alternate picking. The angle of the wrist depends on where and how you are striking the strings. Anchoring the forearm on the guitar body and placing the little finger helps to concentrate all the movement in the wrist. The forearm approach concentrates movement in the elbow. The thumb-and-index-finger approach attacks the strings in small circular movements using only the thumb and index finger. The forearm and wrist remain stationary.
Set a metronome to a slow speed, such as 40 beats per minute, and practice upstrokes and downstrokes with the guitar pick. Gradually increase the speed of the metronome.