Human hair requires care. Your first concern is not allowing it to come apart. Putting 100,000 hairs back together is impossible. Make sure the band is very tight; add one if you are not sure. Combing or brushing should be done carefully.
Tails can be washed. I use a sulfate-free shampoo, and a damage repair conditioner. I wash mine by soaking in a bucket with shampoo and warm water, letting it sit for about 5 minutes, then rinsing in cold water. Then I soak it in a conditioner solution for 5 minutes, then rinsing. I then roll it in a towel, let it sit for 20 minutes to get out excess water, then hang to dry. Hair is most fragile when wet, so detangle most carefully. I sometimes use a hair dryer on low heat.