Before you ever use your griddle, wash it with soapy water, then rinse and dry. Make sure the griddle is completely dry before you use it, however, as you do not want water near the electric cord.
After you use your griddle, use a plastic or nylon scouring pad to clean the cooking surface and the drip tray, and then rinse and dry it again. Simply wipe the heat power cord clean with a damp cloth. Some griddles can go in the dishwasher, so check your owner’s manual to see if your model is dishwasher safe.
If you have a cast-iron griddle, you have more work to do upfront but less work later. Before you use a cast-iron griddle for the first time, you need to season it. Wash and rinse the new griddle without detergent and then dry it over a low flame. Then, use a paper towel to coat the entire grilling surface with some type of oil or fat (not butter). Bake the griddle for one hour at 350 degrees, and finally, remove it from the oven and let it cool before cooking on it.
If you have seasoned your griddle, you don’t need to clean it or add grease it. Whenever food begins to stick to the surface, however, or when griddled food begins to acquire a rusty or metallic taste, it is time to reseason. Wash it again, dry it in the stove and then reapply a thin layer of oil.