The Saturday post at Startup Weekend Columbia focused on implementing the vision and logic for Zapier's product, including backend code, front-end user interface design, and generating a compelling message that describes how users will use the product. The team worked to create a solid user experience, with Mike spending time sketching out wireframes and getting feedback from attendees, while Bryan and Daniel focused on writing tests and implementing the logic for the demo. The message was also developed through a combination of written copy, images, and video, with input from potential users and designers like David Reed and Michael P. Hill. Additionally, the team made an effort to generate excitement around their product by asking for help and offering support to other teams, which helped build relationships and create a sense of community.