Perhaps the only noncliched tip from the Google guys:
“There are people who can be relied upon to respond promptly to emails, and those who can’t. Strive to be one of the former.
“Most of the best—and busiest—people we know act quickly on their emails, not just to us or to a select few senders, but to everyone. Being responsive sets up a positive communications feedback loop whereby your team and colleagues will be more likely to include you in important discussions and decisions, and being responsive to everyone reinforces the flat, meritocratic culture you are trying to establish.
“These responses can be quite short—‘got it’ is a favorite of ours. And when you are confident in your ability to respond quickly, you can tell people exactly what a nonresponse means. In our case it’s usually ‘got it and proceed.’ Which is better than what a nonresponse means from most people: ‘I’m overwhelmed and don’t know when or if I’ll get to your note, so if you needed my feedback you’ll just have to wait in limbo a while longer. Plus I don’t like you.’