Cuora recently posted a comment regarding a spray paint effect tip. http://photoshophelp.blogs.com/photoshophelp/2005/06/spray_paint_too.html#comment-12795034
I don't understand why the red spray paint is only available as red? Or
is this because I'm making a mistake?
No, you're not making a mistake Cuora, just change the Foreground color swatch to make the brush paint any color you desire. The Foreground/Background color swatches are located at the bottom of the tool box. Double-click the swatch to bring up the color picker. Choose the color you want and click OK. I hope this helps.