By default, smooth mesh preview uses the Subdivision Method that is set in the Modeling preferences. This setting is a global preference that affects all new and existing objects in your scene.
To preview a smoothed mesh with OpenSubdiv
Maya displays the original mesh (as a wireframe cage) and the smoothed preview simultaneously, letting you select components on the either version of the mesh.
Maya only displays the smoothed preview. When you select and edit components directly on the smoothed preview, the changes are reflected back onto the original mesh.
Adjust the OpenSubdiv Controls that appear.