If possible remove the batteries and do maintenance charges while not in use. Depending on what kind it may be just every month. Make sure the tanks are dry and put some after run oil in the glow plug hole and put it back in. Then make sure the carbs closed. Store the planes where it doesnt get to cold/hot or humid and that should be about it. There are more secure ways but I dont think its necessary. But if you have loose engines seal em in a ziplock. when you pull em back out in flying season check all of the fuel lines and fire her up. Oh and make sure your tx isnt dead all winter.