For Pega 7.2.1 you do not have a provision to create a new Smart Layout, it is recommended to leverage the Dynamic Layouts.
Note: As a best practice, use dynamic layouts for new development. It is recommended that you upgrade existing smart layouts to take advantage of HTML5 capabilities including cross-browser and cross-platform compatibility, access to the latest HTML markup, and improved performance.
However, to achieve requirements similar to smart layout designs, you can nest/embed a dynamic layout, with a format specified. Such as