It is very important to clean your can openers regularly. One should never put it in a dishwasher as the chances of rusting due to detergent and water are high. To clean it in the right way, soak it in vinegar for quite some time. After it is well soaked, take it out from the vinegar bowl and use a brush to clean the dirty areas. Try using a small brush so that it can reach the smallest of places. Give it a good rinse so that the dirt is gone. Air dry it completely and spray some oil to keep the moving parts working.