ok np ill help u out here man, ok well wat i do when i wanna put a backround is once i put the render i select the magic wand so select all of the white unused blank area, that way colors and brushes dont get on the render, unless i want them to, and i use colors, brushes, filters, adjustments, everything sometimes lol, just mess with it till u get something that goes well with a nice flow, and somewhat is related with the sig (flow), and then i just blend it all together n i have a sig , i never premake my backrounds i always come up witht hem at the spot , well i hope i helped u a bit man, if not look up sometuts at deviantart.com, or IM at lasthope343 (aim)

haha believe it or not i do all this on a labtop too lol, i use photoshop cs2