Hi @meepmeep. Looking at the left hand photos, thanks for posting them.
- I see the wrist crease, to me that might mean that the neck is too low. Try raising the neck a bit more, so there’s not as much of a bend.
- As you get the neck in a more comfortable position, you’ll want your thumb to be more central, behind index and middle finger. This is not for squeezing the neck, it’s more for reference.
- I see a lot of white on your fingertips, are you pressing down hard? You shouldn’t need to squeeze hard at all – try finding the minimal pressure you need.
- I see a lot of palm under the neck, meaning your palm is facing up, and fingers curling around. Try repositioning the neck and hand so the palm is more facing you. The fingers should still curl.
Re breathing and relaxation, my personal experience, some things to think abuot: I used to be very tense when playing, all over, both for guitar and piano. The tension was as much mental as physical. I’m now working out some fundamental things with my guitar playing. One thing I did, as odd as it sounds, was to simply sit with my guitar in playing position, left and right hands in position, and check out where the tension was. The moment I started playing, I had little pockets of tension everywhere. Then I thought about the source of it, and kept releasing it, and breathing into it. Pianists also have trouble with breath and tension, so I tried things like breathing for each downstroke and upstroke.
The above may seem completely useless in your quest to rock out but I don’t think it is. I’ve found that relaxing has opened up my picking, letting me focus my picking. I’m still working on it, and on my left hand, so I don’t have anything impressive to show yet, but it feels like the right way.
Cheers! jz