Dean Wegner outlines a process for creating a "Perfect Purchase Transaction" system using index cards. He recommends bringing together a real estate team to map out each step of the home buying process on individual cards. These cards would then be arranged in order and examined for potential issues or ways to improve interactions. The cards could also be sorted by team member initials to ensure work is distributed evenly. The goal is to visualize the entire process and create a system that consistently delivers a great experience for clients.