I have to say even though I try my best to keep it clean and organised my inbox for home and work is a little messy. They can be very hard to organise when you get so many each week it's very easy to fall behind along with the endless amount of spam emails from those different websites you signed up to all those years ago. I can't promise this will fix your email clutter but let's see what we can do to help.
1. Gmail chat mode
If you are one of those people that sends regular short emails to a couple different people this could really help you out. Gmail has a chat mode also known as Hangouts. In the bottom left hand corner of your gmail desktop screen you can create chats with people, instead of send a whole email to ask a simple question or ask how someone is the chat is a much simpler option that doesn't clog your inbox as much.
This one is pretty straight forward. Use them. Organise your emails as they come in. For example, one for Work, one for school, one for to do's and one for those annoying promo emails. And if your not likely to need it again delete it.
If your one of those people that has kept ever email since they day you made it. This ones for you. For the emails or folders you don't really use anymore but totally may need in years to come use the archive feature and when you need it you can go in and refresh your mind.
4. A great system to use if you are struggling to make the decisions on where to put an email is FAST. File it, Assign it, Store it (Archives) or trash it.
5. Check your inbox at the start and the end of the day as its when your most likely to be in the mood to organise yourself for the new day.