Watch the Three - One Forms online guitar lesson by Brad Carlton from Guitar Lab: The Golden Arp
The final inversion of our three-one forms of the Add 9 arpeggio is 3rd inversion. This also is a very stretched out form. Look at ex 9, measure one. Use your 1st finger for the 5(7th fret 6th string), 4th finger for the root (12th fret 6th string), then slide your 4th finger up two frets for the 9(2). Finally use your 2nd finger for the 3 (11th fret, 5th string).
Keep your hand relaxed throughout all five measures of ex 9. Watch your intonation and strive for a smooth legato sound. Remember to use the higher registers first since the frets are closer together.