Give me your best situational rotation advice

I feel like after watching videos and trying to practice the basics of proper rotation i still get spammed messages about rotating and it has me questioning if there is a universal standard that im still not getting that most players get.

Granted this typically comes from people I see rotating back on the wrong side or jumping from 3rd to first man but im asking because I feel like basic rotating concepts dont fully answer what to do when things happen in real time and i wanna get better. So...whats something youve had to learn when it comes to rotating? Maybe this question is best served by a scenario as an example of mistakes i likely make in game, or not im not sure.

#1 Ball is in opponent's corner. Its you vs two of them, youre outta boost. Do you keep scrapping for the ball? Does 2nd come to help and 3rd sit back? When do you rotate out if at all?

Or here's another - you play 1st lose a 50, ball blasts over 2nd mans head...3rd rotates up as you're going back and 2nd cuts from rotation to 3rd across the field after grabbing boost but you just realize this.

Hopefully im making sense. And maybe i should just watch more games of people who have a track record of doing things correctly?