You can clean your tea kettle by using a vinegar solution. Simply add 1 part white vinegar to 2 parts water and boil the mixture in your kettle. Let the kettle cool, then dump out the solution and rinse it out with fresh water. You can also use this method to descale your kettle if there is build-up inside. Some kettles can also go in the dishwasher. Be sure to check the instructions for your kettle.