I play fingerstyle, and I accidentally made it a habit to shoot my pinky out super far when playing anything, as I don't normally use it. I try to keep it near my other fingers, but as soon as I divert my attention it shoots itself out far away again. It looks horrible and I don't think this is very useful. How can I train my pinky to stay with my other fingers, and act normal? I've been playing a little over a year, and never noticed this until I looked at myself play in the mirror.

I recently started curling my ring and pinky into my palm because of something I saw Jaco do in a video.
But, it's no big deal if your pink flies out, unless you play Sitar.

I wouldn't think the shooting pinky would be a big deal, though I guess that depends on what the mechanics in your forearm and wrist are doing. There might be strain or inefficiency there, or maybe not. To break the habit will take some discipline to -every day- spend time focusing entirely on right hand technique. Play some scales or even a note slowly and evenly, gradually building to normal speed, focusing on relaxing your pinky. I could take some time (weeks or months), but should work. I would guess you'll also build better tone and technique in the process (if you pay a little attention there too).

1-3-2-4 fingering exercises all the way up the fretboard, and 4-2-3-1 fingering exercises all the way down, and vice versa are really helping me train my fingers to work more efficiently across the fretboard.

I've been doing this in octaves and on single strings...and the octave version when said aloud with the notes has really helped me learn where the notes are too.

Add a metronome to the mix and I'm working on my fingering, note recognition, and time - all at once :)

Try using your right hand pinky for muting strings that are not being played. I use this a lot.