If you have not yet setup your inbox to categorize email for you then I highly recommend you do so today.
It's made filtering through my email so much easier for me, and then when it is time for the big purge, again...super easy to get rid of loads of emails in one fell swoop.
So to setup your inbox to auto categorize for you start by:
1. Click on the sprocket or gear on the right hand side of your inbox within Gmail (settings)
2. Click on 'Configure Inbox'
3. Check mark the categories you want to use ( I recommend all of them.)
4. Click Save
Now your emails will be sorted out into these different categories. I have found that very, and I mean very, rarely does some important email find itself in one of the categories it doesn't belong in. Then when you find it there, you can drag it into the category you want it to appear in and then future emails from that address will show up in the category you placed it in.
Why is this so helpful to clearing out the digital clutter, you may be asking yourself...Well, when it comes time to purge email, for me, I find it super easy to click into the promotion category and select them all and send them to the trash folder, same with the forums category (which for the most part are notifications about files shared with me in Google Drive).
I hope this tip helps you get out in front of an overwhelming inbox.