Always use it regularly and avoid those items that must not be put down the drain e.g cooking oil or grease.  When your food disposal is running always make sure to accompany it with running water. It will guide the tiny bits down the drain. It is also advisable to use cold water when its grinding your food scraps.  The cold water will prevent the fats within your food scraps from liquefying – potential cause of clogging. It can keep the fats in solid state unlike using hot water, after the temperature cools down it can solidify these fats and can clog your drain.
You can use hot water when cleaning your disposal unit but it will depend on the cleaning material that you will use, if you are using baking soda, vinegar or some citric acid, using hot water is ideal. But, if you are going to use citrus peels, cold water is much better option.