Start with the next email that you are about to pass over because you just don't have time to read it -- again.  Open it and find the unsubscribe link.  Unsubscribing to just 1 email each time will help clear your Inbox.  And don't keep them coming "just in case" or because "someday you'll have the time to read it".  If and when you find that time, you'll probably be reading other emails. Be strong and unsubscribe now.

You can use filters to automatically move emails into different folders instead of dumping them all into your Inbox.  You can create folders for individual senders (your cousin who sends only jokes or Dhucks' Tips & Tricks) or for groups (a book club or volunteer group).  I find that automatic filters are best for those emails that aren't time sensitive since I may not check these folders every day.  If you are unsure of how to set up a filter, go to your email's Help.

If, and only if, you get overwhelmed by your Inbox or your Desktop, make it a weekly habit to go through them.  Set a day and time that you can and will spend 10-15 minutes each week clearing the clutter.  This time is not for responding to emails but about clearing the Inbox or Desktop.

This suggestion is assuming that your Inbox or Desktop is causing you concern.  I am a strong visual person so I use my Inbox to indicate which emails are awaiting further action and I use my Desktop for files I routinely access or am currently working on.  If you want all your email left in your Inbox or never put anything on your Desktop (like my husband) then there is nothing to fix -- it ain't broke.