Never fear stronger players! 

Good moves win games, not your opponent's rating. Therefore, shift your attention from “Damn, this person is 200 rating points higher than me” to “I’m going to play the best chess that I can.” Most inexperienced players lose psychologically before the game has even begun, but if you focus on playing good chess, you’ll surprise yourself.

Make this important distinction: “Does it look scary?” or “Is it actually scary?” 

Big difference. When evaluating a chess position, figure this out ASAP. A knight on g4 and a queen on h4 attacking your castled king’s h2 pawn is not always scary.

Keep a database of your chess games. 

When you analyze your games, add them to a database. Include your own post-game commentary and analysis (plus suggestions from the engine/computer). Review this often–it will be a treasure-trove of information in the future.

A funny trick: 

Every move, sit on your hands until you figure out your opponent’s threats and plans. Don’t play on autopilot—carefully study the position, then unfree your hands. This funny trick is overkill, but there’s a lesson in there! The only exception to this trick is during speed chess - where playing on autopilot can be useful.

Active learning > passive learning: 

Engage with the material with your full attention. Stop, pause, think, and critique. Watching random chess videos on YouTube or watching chess streamers on Twitch while snacking on popcorn (while fun) won't radically improve your chess—that is, unless you actively engage with the content.

Play against stronger players. 

You will be forced to adapt to their level. Look forward to this challenge! Figure out the turning points in your game, and take note of your mistakes. Pro Tip: If you can, talk to your opponent after the game (much easier OTB than online), and ask how they felt about the game - they’ll reveal important insights.

How to think about chess: 

A game of chess is equal at the start. Your goal is to rack up advantages each move and/or diminish your opponent’s advantages so that you can tilt the game into your favor. The more advantages you’ve accumulated, the easier it becomes to win.