If you have long hair that you’re styling daily and it’s always knotting and matting up you need to start using a leave in moisturizer and serum. Try to find one that’s right for your hair type. Many of these improve the condition of your hair, but this isn’t the main reason to use it. They also detangle the hair and protect it from styling thermals that you use day by day some even adding a finishing shine. Unfortunately using a supermarket brand may not always be the best choice but don’t run out and buy the most expensive product on the shelf. Be very careful to buy the right product, as everyone’s hair is different.
If your hair is fine and limp you may want to avoid it, but if its also very tangled the a light spray leave in treatment is best.
If it is damaged and course then try an Argon or Macadamia oil based product. These have moisturizers and proteins. Try Moroccan Oil products
If your hair is in perfect condition and just gets a bit frizzy just use a shine serum.