Tom LaRock has a list of life-altering recommendations:
RESPONDING IMMEDIATELY
Stop doing that. Trust me on this, your response to that email/text/slack can wait. Don’t believe me? Try an experiment. For one month do not reply immediately to your emails. At the end of the month add up the number of emails you received, and the number of emails that required an immediate response. I’m willing to bet that the number is quite low, much lower than you realize. And once you realize just how few require an immediate reply, you’ll never look at email in the same way again.
It’s a fun list, and I definitely agree in most circumstances on at least 3/4 of them.