Changing the backgroundcolor of the canvas in photoshop
Enlarge your "canvas" (workingarea) this way the gray area around it shows:
Step 2
First pick the paint bucket tool (or press G) and then select a nice color (2):
Step 3
Then press and hold the SHIFT button and click in the gray area around your image. The color of this area changes to the selected color (red in this case):
