Tips for self-studying chess
a) Game analysis in 3 stages: 1. Enter the game text into a database with the variations (and evaluations) that you thought about during the game, 2) Analyze key moments in the game (plan, transition to the endgame, etc.), 3) Go through the game move by move (also helps with opening analysis)
b) Read books without delving into the game text, but like novels... soak up the atmosphere.
c) Opening repertoire: every 200 points, and every 2 years, add one opening for White and one for Black. It's advisable to choose openings that aren't typical for your playing style.
d) Sight-reading!