Extensions are real human hair cut from real people hence it react like your own hair when subjected to too much chemical and lightening process. Therefore it is adviced to use alot of deep treatment products with low ph number. Acidic. 4.4 mostly. When the hair cuticles are already open it best to use product with low ph number to help close the already open cuticles these will avoid tangling and rough texture. Avoid heat and styling product as much. But can still be used once in a while. Moistures the ends quite often and use thin oil and deep treatment twice a week will help.braid your hair loosly or hold as pony tail when going to bed it will help.