I have got Rusty Cooley's The Art of Picking, Shred Guitar Manifesto and Extreme Pentatonics. How should I work on these DVDs to improve my technique? Like for how long should I work on a set of exercises before moving on? How should I use metronome etc.

Would really appreciate your help.
I'd say you should work on any one exercise until it sounds like Rusty playing it.
Bruh? Brah? Breh? Bruae? Bruae.
Work on the exercise until you are satisfied with the speed and articulation of each lick. practice an exercise for 5 minutes, take a 5 minutes break and do it again.
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