Professor Edson Oliveira demonstrates a technique for passing the half guard and securing the mount position, after breaking down the De La Riva. He starts by addressing the importance of a good stance and knee positioning to prevent the opponent from advancing. Edson then explains how to break the opponent's grip and pass to the side, using his hips to maintain control and prevent them from re-establishing half guard. He then shows how to secure an underhook and advance to mount, emphasizing the importance of maintaining pressure and control throughout the pass.