Draw around the buildings with the pen tool to make a path, squared off to the top of the illustration. Join it together to make a sky area – click on Make Work Path > Save Path > Make Selection.
Add a new layer and ensure it is below the texture layers, 1&2 within the background group. Add the colour 31 per cent cyan, 7 per cent magenta, 4 per cent yellow and 18 per cent black. Click on Overlay on the Layers palette.
To make the burger look more integrated into the illustration, click on Overlay in the layers palette, and duplicate it using Layer > Duplicate. On the duplicated layer, select Hard Light with an opacity of 65 per cent. Open the file called flash.eps from the cover CD and click on Path > Make Selection, and paste it into the illustration.
Remove the parts of the buildings and flash that are showing behind the burger layer by selecting the burger with the magic wand and clicking on the buildings layer, then pressing Delete. Now click on the flash layer and delete the area behind the burger.
Create a new layer underneath the characters, and paint on a flesh colour (30 per cent magenta with 20 per cent yellow), using a soft watercolour brush. Do not worry about getting in between the lines. Once painted, add the same colour onto the painted area with the bucket tool, creating a rough, painted-style edge.
Change the opacity on the flesh tone layer to 60 per cent. Select the flesh tone area, and click on the very bottom layer, the craft paper. Paste this onto a new layer directly below the flesh tone layer. This creates a texture underneath, with more depth and interest than just a flat colour.