Deal. Defer. Delete.

It’s a philosophy for instantly dealing with every email to achieve flow. Flow being complete absorption in what one does, focusing at the task at hand & nothing else and seamless moving from one task to the other without mental clutter.

If you keep that in mind, then you should only be focusing on the task at hand, because the any time you spend thinking about doing something and not doing, you’re wasting time and not in flow.
With Deal Defer Delete, you do one of three things every time you see an email. You either deal with it right away (good example of 2 minute rule – if it takes less than 2 minutes, do it now), Defer it — (either via followup.cc or mailbox) until you need to deal with it so its out of mind until it needs to be front of mind, or you Delete/Archive it.

Ive found it best to purge my inbox via batching it (30 min once or twice a day dedicated to email) where you power through all your emails and either deal with it, defer it to when it needs to be dealt with, or deleting it.