I'd honestly stay away from it. I used it for awhile, it's a major pain. You can't spot clean very well, it's very thick, doesn't transfer heat very well, you need at least two pieces for the tank when you wash one of them. If you want something similar, go for paper towels or newspaper. Cheap, simple, and easy to replace

By sanitizing, I assume you mean before placing it in the enclosure? I don't think it's really necessary, but for the moss you can either freeze or drop it in boiling water for about 30 seconds. Freeze or bake for the aspen.