Tapping lesson by Julien Omeyer
Here is what I did for trying to explain how to tap like Buckethead.

I took 6 photos to show the movements I do for tapping on the low E string. The movements are the same for all strings.
Here is the tab for the whole thing, but it's not very important. It can be played anywhere on the neck.
The important thing is that you play semi-tones with each hand.



It's important to notice that right hand plays 16,15,14 on each strings (except B and high E strings : 17,16,15)
and left hand plays 12,11,10 on each strings (except B and high E strings : 13,12,11).

Here is the first photo. It shows the position of the two hands. Your fingers 1,2,3 of left hand are ready to play on cases 10,11,12. With your finger number 3 of right hand, tap the string on16th case.

The second photo shows where this finger (the one who tapped) goes while you hear the note done by your finger number 3 of left hand. The fingers of left hand don't tap the strings, they are just already on the case when the right hand taps. So you hear the note (an E in case number 12) when your finger number 3 from right hand leaves the case after tapping. Important : this finger doesn't go in the direction of other strings, but in the direction of your body.

The movements will be the same for all notes. Finger number 2 of right hand tapping on case 15 :

Finger number 2 of right hand leaving case 15, you hear D# by finger number 2 of left hand, case 11 :

Finger number 1 of right hand tapping on case 14 :

Now, when you've tapped the last note (with your finger number 1 of right hand) you hear the note played with your left hand (a D in case 10). While hearing this note, your finger number 3 of right hand is already going to the case number 16 of next string : string A. You'll hear a C#.

Now you do the same thing on all the strings. Buckethead rarely plays it on all strings but most often on 4 strings.
But for those who like "practicing", that's good to play it on 6 strings. You can also do it from high E string to low E string,
of course... you can do anything you want !

I hope it helps. I hope it's understandable. On some pictures, you can see where I put my pick when I play this tapping thing.
I don't know if Buckethead does that, but that's the best solution I've found for this problem.

Enjoy, and please let Buckethead be an inspiration for you to develop your own unique style of playing!