The most common command you’ll use in the T-spline or Form (Sculpt) environment is the edit form command. To get to the edit form command simply right-click on your selection of faces, edges, points, or a combination of all three. Then, select “edit form” from the marking-menu.

You can also access the edit form command from the modify dropdown list, or by using the keyboard shortcut letter “S,” which will bring up the search box. Then, you can simply search for the term: edit form.