Can anyone recommend me some exercises for the 4th finger? I'm starting to notice it's not as strong as the others, my 3rd finger is ok, but does need more strength.

0-2-1-3-2-4-3-2. I do that exercise up and down the neck on all strings every time I pick up the guitar. Helps with strength and finger independence (at least for me).
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My Rig

Quote by SimplyBen
Wait until he's trying the fullstack, then shove it from behind. Crushing him with it's overdrive

Quote by BobDetroit
You can't tune a LP copies down. Some kind of lawsuit Gibson won. Sorry.
I play 1-2-1-2-3-2-3-4-3-2-3-2-1-2-1 on every string all over the neck for warm-up and it's made my pinky stronger.