hello here are the steps for this product, follow it ,,,,,

steps

- open the file
- drag your mouse or touchpad to the layer list
- find "Your Design Goes Here Layer"
- double click on it ( new photoshop's tab is opened)
- put your design or photo in the tab and custumize the size like you want
- than, CTRL + S or Common + S (for Mac user), it is for saved your design
- the design already changed.

Thank You

