What is the first step to add a curve to a slab or wall?

To successfully add a curve to a slab or wall, the first step involves modifying the selection of the boundary lines defining that slab or wall. When you choose to modify the selection, it allows you to edit the existing geometry and incorporate a curve into the design effectively. This step is crucial because it sets the foundation for making precise adjustments to the boundary lines where the curve will be implemented.

While selecting boundary lines may seem intuitive, it does not account for the necessary changes that may follow. Similarly, selecting the arc radius and setting the radius are actions that would occur after the initial modification of boundary lines. These steps are dependent on first establishing the desired selection to ensure that the curvature is integrated correctly into the overall design of the slab or wall.