If you start right at the beginning and make yourself practice correct technique, you will not run into any of the road blocks that a lot of guitarists encounter after they have played for a few years. Most tend to learn the hard way. They opt for sloppy technique instead of spending the time and effort to get it right from start. I've seen this time and time again. A player reaches a certain level only to have to start back at the beginning and re-learn such things as hand position or picking. This is because improper technique will limit your ability to play like a "mother". In the beginning a player is usually more interested in learning to whip out a few cool songs, but when they try to step beyond that and really play, they find that they can't get the "high performance" that they need out of their hands.
Technique is based on efficiency and economy. Correct positioning and use of the hands is essential in order to maximize your ability to get at the notes that you need to play. I can't stress this enough. Take the time to get it right. In the long run you'll save yourself a lot of back-tracking.
Left Hand: There are two basic left hand positions.
01. Classical (thumb behind neck)
02. Baseball bat (thumb hooking over the neck)
The most versatile left-hand position is the classical position. This is the position we will concentrate on. The baseball bat position is very useful but also very limiting. It will come into play later when we deal directly with string bending, vibrato and certain chords. But, for now, the classical position will allow you to develop the ability to use all of your fingers with equal control and agility.
Try this test:
Place your thumb in the center of the back of the neck. Now, spread your remaining fingers out as wide as you can (With a little practice and relaxation, you will eventually be able to cover 6 frets easily, without moving your hand!). While keeping your fingers spread, slowly move your thumb up and over the top of the neck until you have it hanging over the fingerboard, as in the baseball bat position. Notice what happens to the rest of your fingers. There's just no way to keep them spread out with the thumb hanging over the fingerboard. This fact limits your access to three or four frets at a time with little or no mobility if you flop your thumb over the top of the neck. Another way of thinking about position draws from driving a car. If you've ever taken a driver training course, the first thing they make you do is to put your hands on the wheel at 10 o'clock and 2 o'clock (10-2 position). This is the best hand position for being able to control the vehicle.
Now, nobody in their right mind would go cruising for chicks using that hand position. You'd look like a dork. Instead, you slump down in the seat, crank the stereo and hang your elbow out the open window. Now, you look cool and the babes just can't resist. Right? (My apologies if you take me too seriously here) But, what happens if you're so busy watching for chicks that you find yourself about to get in a wreck? As a reaction, your hands will automatically go to 10-2. Or, have you ever seen a stock car racer whipping around the track at full speed without having both hands on the wheel?
When it comes to playing guitar, especially the rock star variety, nobody wants to look like a dork. So, a lot of players have the guitar hanging down at their knees and grab the neck in the manly, baseball bat fashion. But, with the possible exception of Steve Vai, most of the newer "high performance" players (as opposed to the older "cruisin' for chicks" variety) tend to wear their guitars no lower than waist level, and when they want to tear up the fretboard, sure enough, they pull their thumb back to the center of the neck and stretch their fingers out.
In order to make full use of the classical position, a few points must be observed.
Notice that the knuckle where the index finger joins the hand is NOT touching the bottom of the neck. Many people, when first trying this hand position, WILL anchor this knuckle. Until you develop the musculature of the wrist and hand, it will feel as though you lack any strength in the classical position. Realize that it takes very little actual finger pressure to push the strings to the fret. Most of the tension that a beginner applies with the left hand is directed onto the fingerboard itself and has very little to do with actually fretting the note. To this end, bracing the hand against the neck at the first knuckle of the index finger gives one a feeling of having better leverage with which to "strangle" the guitar. This is unnecessary as, the muscles of the hand will develop in a very short amount of time (usually within the first two weeks).
The thumb should be just a little higher than dead center on the back of the neck and directly in line with the middle finger. (If you take your left hand and touch the tip of your middle finger to the tip of your thumb like those Indian Yoga people do when they meditate, you'll get the idea. Only, don't bend the knuckle of the thumb. Keep it hyperextended like when you push in a tack with your thumb.) Don't allow your thumb to point off to the side like you're hitchhiking as this will destroy the hands natural ability to apply pressure to the strings.
Sitting or standing can make a difference in your ability to assume this hand position as well. When standing, you may need to adjust the length of your strap. If your guitar is too low, it forces you to have to bend your wrist way too much. I tend to wear mine at stomach level, but then, nobody (except my wife) ever tells me how cool I look. I do receive regular compliments on my playing, however.
If you are sitting down, the most common thing to do is to rest your guitar on your right leg. When I first started playing, I found that, if I practiced this way, when I got together with my band, the guitar would be in a different position (I was now standing) and that I couldn't play all those things I was practicing. I started practicing with my guitar sitting on my left leg and propped my left foot up on a book like those classical guitar players do. It made a dramatic difference. Not only was my guitar in the same relative position as when I played standing up, I found that I was able to play things that seemed impossible before.
Whew! There's a lot to consider, but details make a difference.
What follows is an exercise for developing correct hand position and learning to use all four fingers.
Recall the exercise that I had you do in the section on theory. I had you play all the notes, in order, up and down a single string. We're going to do the same thing again only this time, we're going to go across the strings instead of up and down one string. (see file by clicking at bottom).
For the purposes of this exercise, the index finger will play any note on the 1st fret, the middle finger will play any note on the 2nd fret, the ring finger will play any note on the 3rd fret and the pinkie will handle notes on the 4th fret. When playing ascending notes on a string, It's very important to keep any previous fingers that have played on that string holding their notes down.
If I play the F note at the 1st fret on the E-string with my index finger, I don't lift that finger off the string to play the F# with my middle finger. My index finger is still holding down the F note at the 1st fret. If I then play the G note at the 3rd fret with my ring finger, the index AND the ring will still be holding their notes down. The same goes if I then play the next note with the pinky. Now, all four fingers are holding down notes on the same string. This will most likely seem awkward until you gain sufficient coordination of the fingers. Keep practicing. It will come.
Once you have completed all the fingers that are going to play on a given string, then and only then, do you release the fingers to play on another string. Notice the word release instead of lift. To release the fingers is to simply relax the muscles that are being used to hold the notes. If instead, you lift the fingers, you are applying an opposite set of muscles to do a separate and distinct action. This may sound like "nit-picking" but it is very important. Lifting the fingers instead of releasing the fingers is one of the greatest causes of undue tension in the left hand. What happens is that the lifting muscles kick in at the same time that the pressing muscles are trying to do their job. This causes isometric tension in the hand that will slow you down, tire the hand, lead to sore knuckles (personal experience) and generally inhibit you from whizzing around on the fingerboard.
A tell-tale sign of this isometric tension is if you find your pinkie sticking way out there like those people who drink their tea in those tiny little cups, or if you use your pinkie to fret a note and your index finger goes sticking out. Relax, relax, relax! That's the key.
If, on the other hand, you are descending on a given string, you don't have to worry about keeping your fingers down (that would be pretty hard to do anyway), but you still must endeavor to keep the hand relaxed. Use only the amount of tension you need to play the notes cleanly (no buzzing or notes that won't stay ringing as long as you desire).
And another simple way to strengthen your fingers is to rest your hand on a table and practice lifting one finger at a time; easy to do, but it works!