To create color flat plans quickly, you can utilize various software programs such as AutoCAD, SketchUp, or Adobe Illustrator. These tools offer a range of features for drawing, coloring, and annotating plans efficiently. Additionally, you can follow these steps: 1. Choose the right software for your needs. 2. Familiarize yourself with the interface and basic tools. 3. Start drawing your plan by using the appropriate tools. 4. Add color to different elements using the available palettes. 5. Include annotations and dimensions as needed. 6. Save and export your final design.