You can apply a different material to any path, sidewalk or driveway using the quick and handy Materials Paintbrush.
To apply a material to a path element:
Display your model in 3D, and make sure the path is visible in the view.
Select Edit
> Materials Paintbrush, or click the Materials Paintbrush button
on any tabbed toolbar.
In the catalog panel, select the material you want to apply. The Landscape category contains a good selection of pavers, flagstone, gravel and sand.
Click anywhere on the path surface.
Right-click and select Finish.