It's always best to print something small once a week. Even if it's just your name and address in small fonts and different colours. This will stop your nozzles from getting blocked. Leaving your printer on will only help if you use your printer on a regular bases. Epson printers have a build in head clean when you turn your printer on it will do it regardless as to whether you want it to or not. So if you were using it on a regular bases, but, turning it on and off every day, your ink levels will drop as it uses ink from your cartridges to clean the printhead. As you don't use it that often my advice to you would be, turn your printer off but print something weekly and this will help your scenario. Hope this answers your question.