First of all, you have to find someone who can play the erhu, not just anyone. If you find one, it will delay the child's future, which is a big sin. Then you have to have a venue, not necessarily large, or even a room at home, but the environment must be quiet and suitable for one-on-one small classes. If you have a large class, you must have a classroom. I also need to buy some teaching materials, such as erhu graded tracks, and I'd better buy some erhu CDs. You can also sell some related products at the same time, such as rosin, teaching materials and even erhu. I took an erhu class for a while and held an erhu competition. I received a little registration fee, which was not included in my income, for the purpose of publicity.