What should a barber ensure before cutting a client’s hair?

Before cutting a client’s hair, it is essential for a barber to ensure that the client's hair is damp. Cutting hair when it is slightly damp allows for a more accurate and precise cut. Wet or damp hair tends to lay flatter and is easier to manage, which helps the barber see the natural fall and shape of the hair. This is particularly important for achieving evenness and the desired style. Additionally, cutting dry hair can lead to uneven results, especially if the hair has different textures or curls that may not be visible until the hair is wet.

The other options, while they may have some relevance in different contexts, do not directly pertain to the immediate preparation necessary for a hair cutting service. Thus, ensuring the hair is damp is a fundamental preparation step that can significantly impact the outcome of the haircut.