Cut Hair Better, Immediately: Tip #9 of 10
Tip number nine on my list of the things you can do RIGHT NOW to be a better haircutter is to cut with product in the hair. Some haircutters shampoo every client before every cut. Other cutters just hydrate hair by way of a water spray bottle before cutting. Either way most precision haircutters have been trained to cut wet (dry haircutting is a separate discussion).
Cutting with leave-in conditioners or light weight styling products in the hair will make you a better haircutter immediately. Applying product helps the hair to stay evenly damp throughout the haircut. Maintaining the moisture level in the hair helps to maintain even and consistent distribution of the hair. Even moisture levels also help to maintain equal tension as you cut. Damp hair stretches when tension is applied. The degree of stretch is a function of the level of hydration. This makes for a strong argument for consistent tension for better precision cutting.
Cutting with product in the hair causes the hair to behave more like it will as a finished style. This will provide vital feedback as to how the cut is shaping up. You will see the look and the feel of the cut as you cut. Product in the hair also greatly reduces styling time. There is no need to wet the hair to apply product near the end of the cut. Wetting hair for the purposes of drying hair makes little sense. Cutting with product in the hair will make you a better haircutter immediately.