Dont' watch modern media. Dive into old films that stand the test of time. Anything by Godard, Kurosawa, Fellini, etc.

I have awful attention spans, but I find that if I challenge myself by watching stuff out my comfort zone, I'm able to pay attention to it so well. If I know it's a great work of art, I find myself paying attention to just about every single shot, the composition of the frame, etc. It's incredibly rewarding, and it definitely makes watching most modern content impossible now

(That being said, I absolutely loved Pig and The Green Knight from this year)