1. Use the proper shampoo and conditioner—a very mild, not-stripping shampoo, and both products should be sulfate-free and have a low pH.
2. When you wash it, you have to run your fingers through it like a comb, rubbing your fingers through it as you go and kind of squeezing it.
3. If you're not exercising in it and not putting a ton of products in it that are building up and you're taking it off to go to sleep at night, you shouldn't be washing it more than once a week.
4. The best time to comb it is when you're combing the conditioner through the wet hair. Then you let it dry and brush it again. Use a wig brush that's made for extensions and wigs, those little plastic ones work great; a boar-bristle brush works well, too. If you're working out a tangle, you want to start at the ends of your hair first—you should be doing this with your real hair, too—if you start from the top and go down, you make the tangle bunch up more.