Just like natural hair, extensions can also become damaged through excessive styling with hot tools. Extensions can become dried out and brittle. If they become too dry, they'll also become frizzy, unmanageable and eventually break off. One of the best methods of repair involves using a moisturizing hot oil treatment to seal cuticles and split ends, and hydrate hair to keep strands from breaking.
Shampoo and condition hair extensions as usual. Blot out excess moisture with a towel.
Heat up the hot oil treatment by placing it in hot water for about one to three minutes. Test out the oil on a patch of skin to make sure it isn't too hot.
Apply the treatment all over hair extensions. Massage with fingers to make sure the oil absorbs well into hair. Comb through to disperse evenly.
Cover the extensions with a shower cap, or plastic bag, for about five minutes.
Remove cap and rinse out the oil with warm water. Allow extensions to air dry.
Use treatment once a week for best results.