Article in English: This is probably the easiest means of waterproofing a cast, as it takes care of some work for you. You can ask your doctor or pharmacist about cast covers. Many companies sell covers designed to protect casts from water.  Cast covers are usually long sleeves made of waterproof material. You pull these over your cast. They come in different sizes to fit a wide variety of types of casts. Their main benefit is they're far sturdier than other options, making tears less likely. Some cast covers come with a pump that sucks air out of the cover. This forms a tight seal surrounding the cast, adding extra protection. If you don't have a cover, household items can help. Sealable plastic bags can be fit over a cast to keep it safe from water.  Newspaper bags, bread bags, or small trash bags usually work well. You would pull a bag over the cast and seal it on top using a rubber band or duct tape. Rubber bands may be gentler on the skin, and allow you to reuse the bag after showering. Make sure to check the bag for any holes prior to using it to waterproof your cast. If you wrap plastic wrap tightly enough, it can also effectively waterproof a cast. Wrap the plastic wrap around your entire cast, making sure there are no gaps where the cast is exposed. Then, secure the plastic wrap in place with some duct tape or a rubber band. Keep in mind plastic wrap may be less effective than other methods. While it is relatively inexpensive, you may end up with gaps where the cast is exposed. Regardless of the method you use, this is important. Wrapping a towel or wash cloth near the top of the cast keeps water from slipping underneath the cast. Water under a cast can lead to a skin infection.

Summary in Vietnamese:
Mua bọc chống ướt bột. Sử dụng bao ni lông. Thử dùng màng bọc thực phẩm. Quấn khăn mặt hoặc khăn tắm gần đầu phần bó bột.