Online Seminars from Photoshop Tips & Tricks...
Drive the illusion home..
To drive home the illusion of a “raised” button, select a background that is either cooler than the button, or darker. You’ll note that the white background doesn’t help much, and looks more like the button is levitating over the background.
We don’t want that. Buttons don’t usually levitate, so our viewer will have a subconscious, uneasy feeling about the scene. White is going to “pop” around what ever image you put on it. Cooler colors, or darker colors will recede, therefore giving the illusion that the button is “on top of” the background.