Yes, you can use the clean water to wash it. Then you need to prepare the cloth to dry it after you wash it. You just follow the clockwise direction and clean the lenses. It is so easy. You'd better prepare a box for you to put the glasses when you don't use it. Such way will help you avoid the dirty dust.
Well, to clean the tortoise shell glasses, there are some tips you can follow. First, you can use a good quality linen or cotton cloth which will work wonders. And then, you can also use some resolution to clean it one more time. And For the surface of the nose pad, you can also soak them for a couple of hours in warm water to loosen the residue. Also, just gently brush away the unwanted dirt with an old soft bristle brush or old toothbrush. By the way, you should know that tortoise shell glasses are made of tortoise shell. By using tortoise shell, it will make the glasses have a lot of advantages. For example, it will just look beautiful. Besides, its durability and its organic warmth against the skin make people feel well. Anyway, they are cool.