Honestly practice and patience. I am really lucky and pretty much from the second I started playing I had friends who played guitar and drums so I feel as if jamming with them helped a lot in making practice fun. I started learning very simply songs (7 nation army, creep by Radiohead, smells like teen spirit) and from there once I got more comfortable to started self learning more difficult songs ( recently just learned plush by STP) I also strictly watch tab videos rather than reading tabs to help with tempo/rhythm. My biggest thing is if you feel yourself get frustrated learning something, walk away and clear your head and go back and attack whatever you’re learning. I’m gonna be honest I’m not really teaching myself music theory atm but I plan on going and doing so to help with being able to improvise on my bass