List X-Ray

Click on the blue rectangle that shows the number of domains on your contact list

You'll see a list of all your domains sorted by largest number of contacts per domain

Click on the count field to reverse the sort, ordering by smallest domains first. This is often where typo domains, traps, unwanted competitors and spies will be found.

Delete a domain from your contact list by checking the box next to the name and clicking the "Delete Domains" button