The thermal hair cap is the best option if you want to give your hair an oil treatment, nourishing it from the scalp to the ends. How to use: Apply oil to your scalp and massage for five minutes using your fingertips. Then, wear the thermal cap and connect it to an electrical outlet for 20 minutes. After disconnecting the cap, keep it on for another 30 minutes. Finally, wash your hair thoroughly with a sulfate-containing shampoo to remove any oil residue, and moisturize your hair with a suitable conditioner.