Exterior 3D model created using SketchUp and Lumion, you would want to highlight the key features of the scene and the techniques you used to create them.

For example, you might describe the overall layout of the scene, including the buildings, landscaping, and other elements that make up the environment. You could then describe the materials and textures used to create these elements, as well as the lighting and shadow effects that help to make the scene look more realistic.

You might also mention any special effects or details that you added to the scene using Lumion, such as vegetation, vehicles, or weather conditions. These details help to bring the scene to life and make it more engaging for viewers.

Finally, you might describe how you used Lumion to create a fly-through animation or a 360-degree panoramic view of the scene. This allows viewers to get a better sense of the environment and experience it in a more immersive way.

Overall, your description should aim to showcase the key features of your exterior 3D model and demonstrate your skill and creativity as a designer.