i know no theory whatsoever, just the practical side, by watching someone else play, then copying them, or getting them to teach me, and then just practicing it everyday.
we actually played Layla at one presentation evening.
there was a pupil who was very good on the keyboard, so he basically arranged the whole song on the keyboard and computer, then used the 3 of us (me, my mate and the maths teacher who taught us) to provide the guitars and bass.
i played the lead guitar, with my mate doing the chords and teacher doing the bass, but unluckily for me, on the very first time of doing the riff, my top E string broke!!!
so me and my mate switched parts, cos we had learnt both anyway.
and it was the full 7 or 8 minute long version, with the piano bit too.
RIP Jules, never to be forgotten. #KeepFightingMichael