I want to start economy picking, but I've got absolutely no idea where to build the technique to do so.

Could anyone suggest some exercises for it please?
Pick an easy exercise, like a bit of a solo you can play well, and work on playing it, speeding it up gradually using a metronome.

You've got to cross strings, obviously. Basically it is cheating. It is up-down-down-up-down-down as you cross the strings.
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