It's not neccessary, but you should try to put your thumb over the fret board and when doing a vibrato..imagine yourself turning a knob to open to close...to open.... to close.
Co-Founder of the Orange Revolution Club

-Esp/Ltd Ec-1000 w/ BKP Mules
-2-channel Titan
-Oversized Bogner 2x12 Cabinet
-Fulltone OCD
-RMC Picture Wah
-T.C. Electronic Nova Delay
-Larrivee D-03R
go to guitarplayer.com or atleast thats what i think it is just google guitar player magazine
then go to guitar player TV and theres tons of cool lessons and stuff
Parkwood PW320M
Epiphone Les Paul Standard
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Squier Strat
Some beat up acoustic from '68

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