For a very long time I could not play fast. As a result, I've learned pretty much everything else about music. I can play a dozen instruments and I know I whole lot about music theory and all that stuff. But then I finally set my mind on learning how to shred. In my opinion, even though tapping, legato, and sweep picking are important, alternate picking is most important to being super awesome at guitar.
The first thing I did was buy a whole bunch of different picks. It's pretty easy to go to a guitar shop and spend five dollars on every size and thickness of pick. Don't just get a bunch of the normal shapes. Get a tiny nylon jazz pick, an even tinier teardrop shaped pick, some metal and plastic finger picks and thumb picks, and the ones that fit under your fingernail. There are also picks with suction cups and picks the size of small stones. I didn't just try a bunch of these and stick with one. I switch between all of them, and I get better using all of them.
Then I started focusing on precision. I have an HM strat with a bare humbucker and two single coils very snug together and maybe a half inch underneath the string. It may be different for those playing on Gibsons with like an inch of space between the guitar and the strings, but I have to make sure to use just the very tip of my pick or I tap the pickups. Not only does it sound bad and slow you down, but it's just like when something tickles the rim of your nostrils, it just pisses you off more than anything else.
The most important thing I did, I believe, is something that, so far, I haven't heard anyone really mention in lessons. I developed and then learned to control a bounce in my picking. It was not intentional, at first I just gave up on my wrist and began to pick strictly from my elbow. If you think you can get precise with this I would say go ahead, because your elbow is probably already a whole lot faster than your thumb joint and especially your wrist. Just be aware that you might injure yourself, and then everyone would laugh.
So I started picking from my elbow, and I was going to stick with that, but I noticed that my wrist began to bounce like I was knocking on a door, and I am now exploiting that. Also, I hold my pick at very specific angles to make the bounce consistent. The bounce at first came from my elbow, but now pretty much comes from an oscillation in my wrist.
This is where the technique ties in with drumming. Drummers use their wrists to swing the stick down onto the drum. The drum stick bounces of course. Drummers learn how to control the bounce to get faster. You should learn how to get a bouncing motion in your picking, and then you should learn how to control it. At this point alternate picking across strings won't affect speed at all, because all you have to do is let the pick hit the string, bounce right over the next string without any extra motion, then turn around and pick that string.
So this all comes down to how I pick and what exercises I use. I slice the string just a little bit. I make my downstroke with the left side of the pick, my upstroke with the right. The second angle, the rotation of the pick inside my fingers, doesn't matter that much. The point of the pick can be directly toward the string, or rotated thirty or so degrees either way. The third and angle is tough to explain. Imagine looking up a string from the bridge to the nut and seeing only the thickness of the pick, completely vertical over the string (not that it would be when combined with the other angles), now imagine rotating this angle forty-five degrees clockwise. So yeah, slice the string a little, and don't hold the pick perpendicular to the string, tip the point up toward the ceiling.
All of this would make a perfect down stroke, but a terrible upstroke IF you were just moving your wrist down toward the floor and up toward the ceiling. Don't do just that. You should also pick down into the strings just a little bit. This makes the attack more clear and increases precision. Rotate your wrist so you can see your palm a little bit, and then pick down, and also in; up, and also away. Kind of like you were knocking on a door. Think of picking the highest string from the side completely. Picking right toward the guitar and away. Now think of picking right toward the floor and the ceiling. Your wrist should be directing the pick partially toward the floor, and partially toward the guitar. Then partially toward the ceiling, and partially away from the guitar.
That is how I pick and how I hold the pick. ALso, my fingers are very relaxed, though I don't drop the pick. Remember to seek the bouncing feeling. Now to the exercises.
After I began to pick this way, my right hand was too fast to keep in sync with my left hand. My left hand is still faster though, of course. So in order to really sync up my hands, I make sure to alternate pick one hundred percent. Eventually it becomes so natural that your pick just bounces to the other side of the string on it's own, and it is a wonderful feeling.
I double picked, meaning that I picked each note twice. Make sure to start on an upstroke as often as you start on a downstroke. Also try triple and quadruple picking. Once your right hand is up to speed, normal picking is useless because you are now working on coordinating your two hands.
These three exercises help a whole lot:
This is an F/D arpeggio that really helps with moving from string to string. Remember: alternate pick, single and double pick, start on up and downstrokes. Use only the very very tip of the pick. By the way, this is the first five string sweep I suggest you learn (hammering on and pulling off the eighth fret on both ends).
E||-----------------5--8--5--------------||
B||--------------6-----------6-----------||
G||-----------5-----------------5--------||
D||--------7-----------------------7-----||
A||--5--8-----------------------------8--||
E||--------------------------------------||
The next exercise is simple chromatic picking. Pick frets one two three four then move up a string. You can come up with a million variations. Pick one, two, three, and four notes on a string in different orders. This will really help with coordinating your two hands.
The last exercise is a Paganini phrase used in Eugene's Trick Bag. Make sure to alternate pick, and double pick up down and down up. This is a good benchmark exercise. You can impress almost anyone if you can get this faster than 150 bpm.
E||-----------------------------17-15-13-------------||
B||-----13-17-13----15-17-15-13----------17-15-13----||
G||--14----------16-------------------------------16-||
D||--------------------------------------------------||
A||--------------------------------------------------||
E||--------------------------------------------------||
Another two btws. Use a metronome most of the time. It is good to play without one probably ten percent of the time so you don't get too used to it. And remember that shredding does come down to muscle memory. You have to play something a thousand times to really get in your hands, then another thousand for every five or ten bpm.
Here's the first part arranged of Eugene's Trick bag to look as cool and be as difficult as possible. Your hand jumps around just as much as in the movie.
E||------------0----8-12-8----0---------|-----------------------------------|
B||----------1---10--------10---1-------|------------0---9-12-9---0---------|
G||--------2----------------------2-----|----------1---9--------9---1-------|
D||------2--------------------------2---|------0-2--------------------2-0---|
A||--0-3------------------------------3-|----2----------------------------2-|
E||-------------------------------------|--4--------------------------------|
--------------0--------0-----------|
------------2---8-10-8---2---------|
--------0-2----------------2-0-----|
------2------------------------2---|
--0-4----------------------------4-|
-----------------------------------|
---------------------10-13-10------------------|
------------------10----------10---------------|
---------------10----------------10------------|
------------12----------------------12---------|
--0----8-12----------------------------12-8----|
----10--------------------------------------10-|
---------------------------------------------|
-----------------------12--------------------|
-----------------10-13----13-10--------------|
------------9-12----------------12-9---------|
-------8-11--------------------------11-8----|
--7-10------------------------------------10-|
----------------0----------------12----16-|--17----------------||
------------1--------------13-------13----|--------------------||
--------2-----2------14-------14----------|--------------------||
----2-----2-------------14----------------|--------------------||
--0---3-----------15----------------------|--------------------||
------------------------------------------|--------------------||
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. There was a song that a friend of mine played at a cast party, which I thought was really sweet, and I have found the music to on this site...only problem is that I don't know how to read, let alone play, chords. The song is called "A better Version of You" and is by Paul and Storm." If you or anyone who reads this could help me out, I'd greatly appreciate it. Thanks ahead of time 
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