I have a blank .png of the circle ring. Utilizing gimp I open up the .png along with the players portrait, resize their portrait and the paste it into a new layer. Pop the circle ring up a layer and then utilize the magic wand tool and select everything outside the ring on the ring layer. Afterwards I shift down to the portraits layer, while making sure everything outside the ring remains selected. I hit delete then save it as a new .png and upload.