practice alternate picking with a metronome and keep getting faster and faster
Tremolo picking is basically alternate picking with a faster motion ( more relaxed too ) so just practice alternate picking ( like said ) with a metronome until you can play at faster speeds.
you could try slanting your pick so it slides over the string more easily. not sure if this effects the crispness of the sound.
On tremolo picking, start at slow pace. Never rush into tremolo picking or you're not gonna get it down smoothly. Try it slowly, then once you can build up some speed, try using slight palm mute.

NOTE: If you're just beggining, I don't recommend starting off with tremolo picking ,soloing, etc.
Definitely using the wrist is superior for picking (everything), doing it from the elbow can definitely cause tennis elbow due to repeat movement of joints, thus wearing out the sinovial sac. it can also cause tendonitis(same for wrist too, if improper exertion).

Using the wrist, will definitely get you much further, doing it from the elbow can make you tire out very quickly, tense up and perhaps damage some of the muscle fibres.

If your technique is improper from the wrist, then you will get Carpal Tunnel Syndrome, probably the most common injury that musicians get(yes, even vocalists )

If you relax, use your wrist, then elbow movement is not needed.

RELAX! All your problems will be solved.

That's all I can say. I use to ask my friends and my dad how to do it , they just said practise. So I sat down and watched Tv and played the guitar and then I finally got it after a while.
also, try holding the pick power down, so the pointy bit is only sticking out a little bit

this prevents it getting caught in the strings

also learn either the solo to paranoid android by radioheadf or platypus i hate you by green day to get you used to that type of speed
It came pretty naturally for me, just play your guitar, all the time, and soon when you apply yourself to tremolo picking, it will work out.

I naturally figured out these steps, and that's what works for me

1.)Use the very tip of your pick. Don't let more that a millimeter of the pick drop below the surface of the strings.
2.)Angle the pick a little by bending your thumb slightly. This will help the pick glide across the strings more smoothly.
3.)The side of your thumb will gently brush against the surface of the other strings, while the pick drops just below the surface.
^ ^
(off of cyberfret.com)
Last edited by walk_down at May 27, 2006,
Dont do this all the time but if you're having a lot of trouble, pick the strings just at the bottom of the neck of the guitar, like, on the very last fret, as your pick is much less likely to dip too low and catch the strings, resulting in you slowing down.
kepp a loose arm and a steady rhythm when I first started I was like how can anybody do this so fast but after practicing I got pretty good at it and now I can go pretty fast