In this lesson, the focus is on hair rollers, specifically their different sizes and how to use them effectively. The instructor discusses the importance of understanding client preferences and hair types when selecting rollers, explaining that larger rollers provide more lift and movement, while smaller ones create tighter curls. Additionally, the lesson emphasizes the need to properly dry the hair and use protective products to ensure the hairstyle lasts longer. Overall, the importance of client consultation and tailored styling techniques is highlighted throughout the session.