How do you train your little finger to stay in line?
Of all the exercises I've come across this is the one that I find works the quickest, on getting the 4th finger to stay under control. I'll warn you its not easy at first, but you don't have to be brilliant at this exorcise to get some very quick improvement in 4th finger control, as long as you do the exorcise correctly. When eventually you can do this exorcise well, you'll find you have complete (or as complete as you can get) control over your 4th finger.
So here's the exercise:
1) Hover your 1st, 2nd and 3rd fingers a millimetre or two over the B string, each finger hovering over its own fret ie: the 7th, 8th and 9th frets.
2) While keeping these three fingers in place, hover your 4th finger a millimetre or two above the A string at the 10th fret.
3) Rule: you MUST keep your 4th finger hovered a millimetre or 2 over the A string 10th fret (and curled slightly) AT ALL TIMES. This is the most important thing, all other parts of this exercise are secondary. In other words, none of the exercise will work unless your 4th finger is in this position at all times.
4) Put your 1st finger down onto the 7th fret (B string), but you MUST keep the 4th finger hovering just over the A string. Its no good pressing down with your 1st finger and your 4th finger moving away from the A string, and then getting it back quickly. The 4th finger MUST stay a millimetre or 2 above the A string the whole time. if it takes ages to slowly get your 1st finger down onto the fret while keeping your 4th finger in position, this is fine - you will be getting benefit from the exercise. If your 4th finger moves away from the string, even for an instant, you are not getting anything from the exercise, so you have to start again.
Note: As I said before, it is not necessary to be able to do this exercise easily, to improve control of your 4th finger, only that you do the exercise correctly.
5) Keeping you 4th finger in place, release the pressure of your 1st finger (no need to actually lift it off the string) and press your second finger down on the 8th fret B string (which it should have been hovering above up till now). As always, you must keep your 4th finger hovered just above the A string the whole time. If your 4th finger moves away, even for an instant, you must take your 2nd finger off, put your 4th finger back in place, and try again.
Note: it doesn't matter how long it takes to get your 2nd finger down (its fine if it takes several minutes) just as long as you keep your 4th finger hovering just over the A string the WHOLE time.
6) Release the pressure of your 2nd finger, and press your 3rd finger down onto the 9th fret. As usual, keeping your 4th finger in position the whole time.
7) Go back releasing 3rd finger, pressing down 2nd, releasing 2nd, pressing down 1st, then back up etc... Don't forget, if you let your 4th finger moves away from the A string even for a second, its no good just putting it back and carrying on - you've got to start again.
8) pay particular attention to the movement between the 2nd and 3rd fingers, this is the most difficult time to keep the 4th finger in place.
Note: Keep your hand relaxed. This may seem like a contradiction in terms when you first do this exercise, but most people find that if they relax enough, for long enough, and concentrate for long enough, it gets a lot easier to do this exercise than if you just let your hand get really tense.
By the way, although for the purpose of simple explanation I've asked you to do this exorcise over the 7th, 8th, 9th and 10th frets, you can do it anywhere on the neck as long as the frets use choose are consecutive and you use the B and A strings.
Once you've been working on this exercise regularly for a couple of weeks (IF you've done it correctly ie: kept the 4th finger in place at ALL times), you'll start to find that you can keep your little finger nicely curled and in position in line with your other fingers, even when its not being used.
Remember, in time it will seem like the most natural, relaxed thing in the world to keep your little finger in control - you'll forget it was every out of control.
NEVER attach anything to any of your fingers to hold them in place or change their position - you'll very likely damage your tendons if you do.
If you ever experience any sharp or serious pain: relax, stop the exorcise and try it again in a day or two. You should never carry on with any exercise if it it causing any real pain. Having said that, there is no reason why this particular exercise should cause you any pain (unless you've let your hand get extremely tense).
Once your getting some control over keeping your 4th finger in position you can do these exercises.
The number refers to the finger number, and the letter refers to the string. These exorcises can be (and should be) done everywhere on the neck. Just make sure that you are using 4 consecutive frets, one for each of your 4 fingers.
Pick each of these notes (might as well use alternate picking too).
E1, B2, E1, B3, E1, B4, E1, B3, E1, B2 repeat...
E2, B1, E2, B3, E2, B4, E2, B3, E2, B1 repeat...
E3, B1, E3, B2, E3, B4, E3, B2, E3, B1 repeat...
E4, B1, E4, B2, E4, B3, E4, B2, E4, B1 repeat...
B1, E2, B1, E3, B1, E4, B1, E3, B1, E2 repeat...
B2, E1, B2, E3, B2, E4, B2, E3, B2, E1 repeat...
B3, E1, B3, E2, B3, E4, B3, E2, B3, E1 repeat...
B4, E1, B4, E2, B4, E3, B4, E2, B4, E1 repeat...
If you want to take this further, once these exercises are getting easy, you can do them skipping a string or even 2 or more strings eg: instead of using the B and E strings you could use the G and E strings.
Note: if you alternate pick these exercises, they are excellent for the picking hand as well.