[duplicate closed] How to add border within canvas size in Photoshop

[stefanb88191817]

Hi all,

I am trying to add a border within an a4 canvas without adding it onto the overall canvas size. I have an image I would like to shrink down inside the canvas. 0.5"/1" borders I am trying to add.

I looked around but the only tutorials are for cropping images with a border on the top or adding onto the canvas around the outside. 

Thanks!