The reason for brittle hair is that it lacks moisture either from the environment or from inactive sebaceous glands. It is also recommended to drink lots of water, eat more protein and take vitamins (Zinc, Omega 3 and vitamin B) to make hair stronger and healthier looking.
TIP: if you colour your hair look for hair dye that is free from Ammonia which is harsh on hair.
Step 1 - Cleanse
Cleanse the scalp with a gentle cleanser that is free from fragrances and Sulfates (harsh detergents).
Step 2 - Conditioner
Use any conditioner that is recommended for your hair type. Do not place conditioner on your scalp.
Step 3 - Weekly Treatment
Weekly hot oil treatments do help and should be used with every shampoo at the beginning until the hair is healthier then reduce to once a week. Always include a leave in thermal protector if you blow dry, flat iron or curl hair often.
Step 4 - Sunscreen
The sun does deplete moisture from your hair so as much as possible stay out of direct sunlight or wear a hat.