Not that often, but a little daily maintenance goes a long way in preventing having to do a 'full' cleaning. After initially putting a little amount of noalox on the switch contact, really maintenance is only whenever you notice a change in performance. It only takes about 10 minutes to pull the switch out, clean the entire barrel and tips, replace the noalox, and put back together. Drew has a how-to video here on one of the sticky
threads.
Daily I just wipe down the tips and atty's when I change them or am putting it away for a while and the threads whenever I change
batteries with a dry cloth. Other than that, it is pretty hassle free!