Follow these steps carefully.
First open up your PSD that you have just uploaded from a site.

Copy the psd by simply hitting ctrl c and now open a new document a little bigger than the PSD.

Now flood fill the new document with the color you would like the outline to be.

Next you are going to paste the PSD as a new selection edit>paste>new selection to the color document.

There will be a moving border around the PSD do not get rid of this border yet!

Now you are going to expand the border by going into selections>modify>expand .

Now just leave the moving border around the PSD and copy ctrl c the PSD and paste it as a new selection on the graphic you would like.

I hope this helped!