1. First open the SketchUp model, and you can view the document size of the model in "Window-Model Information-File".

2. Deleting the useless model and deleting the useless modules in the model can quickly reduce the model size and speed up the operation.

3. You can also open "Window-Vehicle Information-Statistics" and select "Clear Unused Items", which will obviously improve the operation.

4. Then open the "window" and select "Edit", and then tick off all useless options, only the edge is enough.

5. Finally, after cleaning, it can be saved.