PSD models tend to use “Photoshop Smart Objects” to allow the end user to change the design within the layout. Open the file and you will find
the “EDIT THIS” layer, then double-click on the “EDIT THIS” miniature to change the design. Once you’ve added your design, save and close the file. When you return to the main document you will see your design that has been transformed and placed in position within the mockup layout.