Cantilever coping comes two ways
With both options you can just install over the pool or pool and step. If you choice to install over the pool and step make sure the step is a cantilever step. If you choose the cantilever with foam forms you will need to complete the concrete deck before installing the vinyl liner because the form will connect in the liner track until the concrete completely dries and then remove the forms. Don’t throw the forms away because they are reusable. When choosing the cantilever for bricks or stones option you can install the liner first.