If you use your copper still for distilling moonshine, whiskey, etc at least several times a year, you will only need to clean it with a water distillation.
Using your copper still regularly can cause it to turn a deep red color due to oxidization. To prevent it polish the outside with an non abrasive polisher, making sure that it contains no harmful substances. There are traditional methods, of course, that you can use to clean the pot: moisten a cloth in a solution of salt and lemon juice and rub this over the pot. Proper maintenance of your copper still after distilling moonshine will ensure a long life for it.