Tea tree oil is an all-natural and highly-effective cleansing agent available at your local drug store or health foods market. Pour one cup of warm water into a medium sized bowl. Add a few drops of tea tree oil and stir to combine. For those with sensitive skin or allergies, using your own shampoo, plus baking soda, is a safe and gentle option. Pour one cup of warm water into a medium sized bowl. Add a teaspoon of shampoo and a teaspoon of baking soda and stir to combine. Using a clean toothbrush, dip the brush end in the solution. Make sure that the toothbrush bristles are completely soaked with the cleansing agent. Take the toothbrush and brush the cylinder or pad from the base, where the bristles are connected to the brush head, all the way to the top. This will remove oil, dandruff, and leftover hair product. Move around the hairbrush methodically to cover the entire surface. Make sure to include small circular motions to help dredge up heavily soiled brushes. After scrubbing the bristled brush cylinder or pad, dip the head of your hairbrush into the cleansing agent. This will help to remove any loose particles, as well as provide a second rinsing, which is particularly useful on stubborn hair product build up.  If the hairbrush has a wooden handle or paddle, do not submerge the brush in the water. Most wooden brushes are coated in a moisture repellant, but they aren’t 100% resistant. Instead of submerging in the bowl of water, perform one or two additional toothbrush cleanings. Fill a second medium sized bowl with clean and cool water. Lower your hairbrush into the water gently submerging the entire bristled area. For circular brushes, you may have to twist your brush in your palms to make sure the entire area has been rinsed. If you have a wooden bristled brush, hold the brush bristle side down over a sink or a towel. Take a mist or spray bottle and soak the cleansed bristles until the water runs clear from the bristles.

TL;DR in Chinese:
用茶树精油作为纯天然清洁剂。 敏感皮肤可以用洗发水和小苏打作为清洁剂。 用干净牙刷在清洁剂中蘸湿。 刷一刷鬃毛梳梳齿之间的缝隙和梳板。 将鬃毛梳泡在盛有清洁剂的碗中，以便清除残留的污垢粒子，完成深度清洁。 用干净的凉水清洗梳子。