Tools, Tips, Technique
Tools: Serum usually comes in a small bottle with a pipette for dispensing the serum in droplets or very slowly. But serum can also be found in tubes as a cream. It is available in many qualities and strengths.
Tips: Always be careful with serum and don't use too much. I usually add it drop by drop so I can control the shine and the hair does not become oily. In my experience some serums are better for styling, others more effective for a deep hair treatment.
Technique: It is very important to rub the serum or oil in the palms of your hands first and then run the palms of your hands and fingers through the hair. Applying the serum or oil directly to the hair from the bottle can result in large oily patches.