This is a lesson that introduce you to tapping and some exercice to
improve it...let's start:

-right hand;play directly on the fretboard on the fret you want to play
with your index and put the middle finger across the index to strenghten 
this last one(the middle pushes the index that pushes the string
and it will work really better!!)holding your hand on to the
freatboard with the thumb:

-left hand;this hand works with hammers on and pull off........

This is the 1st ex:(triads)

r:right hand tap
l:left hand tap

   Hammer on part                 Pull off part 
   r  l l    r  l  l    r  l  l    r   l l    r   l l    r  l l
G-12--5h9---14--7h10---16--9h12-|-16--12p9---14--10p7---12--9p5---
D-------------------------------|---------------------------------
A-------------------------------|---------------------------------
E-------------------------------|---------------------------------

move both the hands on the fretboard(up and down)to improve your technique
and you'll get the speed automatically little by little....
it's important to have a clear sound during the execution!!!!
You also have to get a nice coordination between the hands,and 
this exercices will work 4 you:

  r l l  r l l   r l l  r l l   r l l   r l l   
G-8-7h8--8-7h8-|-9-7h9--9-7h9-|-10-7h10--10-7h10-|make the same with
D--------------|--------------|------------------|pull-off
A--------------|--------------|------------------|train all the fingers
E--------------|--------------|------------------|of the left hand!

the exercice above is divided in 3 parts:
-in the first part you have to use the index and the middle of the
left hand(just the index of the right one)
-in the 2nd part you have to use the index and the ring finger of the
left hand(just the index of the right hand)
-in the last use index and pinky.(as above)
When you're mistakin you get it because fingers of different hands hit
each other and this mustn't happend to play tapping correctly!

Then you can also play using the left hand like a capo:you put fingers of 
the left hand on the desired frets then tap with the right hand
and release,you'll get two different notes....ex

  r  l r  l r  l r  l r  l  r  l  r  l  r  l  r  l  r  l  r  l  r  l  r 
G-12-9-12-9-12-9-12-9-14-11-14-11-16-12-16-12-17-14-17-14-19-16-19-16-21---
D--------------------------------------------------------------------------
A--------------------------------------------------------------------------
E--------------------------------------------------------------------------

this is a nice progrssion on Em,but you can also play chords ex:

   
  l     r  r  r  r  r   r 	  l r   l  r   l  r  
G-14----------21-17----------   G-9-16--12-19--14-21----                                          
D-14-------17-------17-------   D-9-16--12-19--14-21----                                 
A-12----15--------------15---   A-7-----10-----12-------                                          
E----------------------------   E----------------------- 

with the left hand keep pushing the string down and in the meantime tap
with the right and release;you'll get the note played by the right hand
and the left and too...here you have to pratice a lot too to get the speed!
remember to do this it's the most imp. ex.

  l   r r  r  r  r  r  r   l   r  r  r  r  r  r  r  
G-16--9-10-11-12-11-10-9---19--12-13-14-15-14-13-12-- and repeat
D----------------------------------------------------
A----------------------------------------------------
E----------------------------------------------------

this really strenghten your left hand and once you can use all the fingers
of your left hand you won't have problems anymore!
Well I hope this is helpful to anyone and i also hope that it's clear..
4 everything send an e.mail to nicholasberti@hotmail.com
I just add that you can invent a lot of exercice(like i do,i never had bass
lessons) and put some good tapping
riff in your song...it's not just 4 guitar!!