Alternate Picking Chart: Follow this for best right hand technique and good form

source : effective-lead-guitar.com
If the smallest rhythmic value is a quarter note, you don't need alternate picking at all!
If the smallest kinds of notes are eighth notes, use down picks on the numbered beats (1-2-3-4) and up picks on the "ands," BETWEEN the beats:
If the smallest kinds of notes in the phrase are sixteenths, then use down picks on the numbered beats AND the "ands," and use up picks on the "e's" AND the "a's."

Reminder

Use a metronome when practicing these examples. Start out slow and gradually increase your tempo. In addition, make sure you use the suggested fingering below the TABS.

The real key to learning how to improve your alternate picking and right hand technique is this: if you subtract any of the notes from the phrase, you still have to maintain the same down/up alternate picking pattern as if the notes were still there!
This is where the TRUE masters of alternate picking and speed guitar technique emerge! When a note is subtracted, you have to MISS the string and PRETEND to perform a picking motion. This resets your direction and maintains continuity throughout the phrase. DOWN where down should be, and UP where up should be.
The perfect way for us to learn this concept is with the galloping horsey riff, a la Metallica, in which the "e" -- the second sixteenth note out of every group of four sixteenth notes -- is removed. If you count sixteenth notes this way:
1 e & a 2 e & a 3 e & a 4 e & a... ...Then it is the e beats that we will remove and thereby MISS the stroke.
Like every rule in guitar, there is an exception to the rule. There is something called economy picking, but we will have a separate lesson for that technique as it falls out of the scope of this lesson. But for now, just know that there ARE cases in which you may forgo the strict alternate picking pattern in favor of ECONOMY picking.