Brushing wigs is really easy. If you don't have a wig stand or head to pin it too, have a family member model it temporarily for you.
1. Spray the wig with water or leave in conditioner(detangle-er). This is how I was taught to start out with my American Girl Doll's hair. It gets rid of the static built up in the hair and stops the strands from sticking to each other. And if you use the conditioner, it provides even extra lubrication for the next step.
2. Comb the hair with a steel pronged wig brush or a WIDE tooth comb. Start at the ends of a section of hair, brushing out the tangles. If a knot is just too tough, snip out the knot with a pair of hair scissors. After the ends are done move up toward the cap. It really shouldn't be too tangled the farther you get up the wig. Just be patient and gentle with your brushing and everything will be okay. Sure some strands will snap, but so does your real hair at times.
When you're finished, I would suggest taking a scrunchie (not a rubber hair tie) or a ribbon, something made of cloth, and gently put it into a pony tail like half way down the length of hair, not right up at the cap like you would with your own hair. This will stop it from getting tangled.
Personally, I don't have room to display my wigs in my tiny one bedroom apartment, so I bought gallon ziplock bags and put my wigs in them so they don't get tangled, squeeze all the air out of them and close them. Nothing has happened to them. This is also how I transport them to con because I don't like wig heads moving around in my car. This doesn't work for spiked/gelled wigs of course, but then again those wigs don't have to worry about tangling in the first place -_-