A comprehensive and up-to-date Knowledge Base can solve two of the biggest helpdesk problems - having a single place to share solutions ensures consistency among them and, since customers can access the kbase and find their own solutions, they feel more confident about your business. Oh, and all the while, your support load reduces too.
Once you've populated your Knowledge Base entries, you can set up your support portal to Auto-suggest solutions that are in line with a customer's query before they submit a ticket.
You can enable Auto-suggest from Admin > Portals > Settings.
Through this Auto-suggest feature, a customer trying to create a new ticket from the portal can view relevant solutions, thereby saving both of you time as well as effort.