A healthy diet is said to help. Vitamin E is going to make your hair look shiny silky and reduce frizz. Do not use straighteners, curlers or any other kind of heat stylers. Use a very low heat setting on hair dryers. This should help.
If yo use heat styling then make sure to always use heat protectant beforehand to prevent damage and makes hair soft and healthy.
Get a good haircut to take off most of the damaged hair.