Clutter moves your low priority messages out of your Inbox so you can easily scan for important messages. Clutter analyzes your email habits, and based on your past behavior, it determines the messages that you’re most likely to ignore. It then moves those messages to a folder called Clutter, where you can review them later.
The folder is located under your myMail inbox on the left-hand menu.
While in the clutter folder, right-click the message you want to move to your inbox and choose 'Move to Inbox'.
If you want to move a message to the clutter folder so future messages go there from that sender, right-click the message in the inbox, choose 'Move to Clutter'.
Click the gear in the top right, choose 'Options.'