We don't recommend alcohol, or any other chemical products, it will kill your atomizer. We recommend blowing
through the atomizer and dripping a few drops of liquid after this simple but effective cleaning method. The dripping is to soak the atomizer.
Dry atomizers smoking will overheat and burn the filament inside, resulting in a burned taste and eventually defective filament. Dry smoking is tricky and can result in defects if you dry smoke too long. Always check your atomizer for overheating when doing this!
If you use different sorts of liquids with the same atomizer, especially bad quality liquids, the only thing you can do is rinse the atomizer with water and blow through the atomizer and repeat this like 20 times. Then dry blow with a hairdryer, drip a few fresh drops of good liquid, then about 5 puffs and you should be good to go again.
Keeping you atomizer vertically at night when the cartridge is half full or horizontally if the cartridge is still full is also a good trick.
Over dripped atomizers should be kept vertically without cartridge, on a tissue paper or on the dry rack overnight.
None of these methods is guaranteed all the time of course.