A neat method to adding color, shape, and even texture, includes the use of stamps. However, you may find the world of buyable stamps lacking in pagan themes.
This site, Fifth Wizard, offers the nifty idea of using plasticine (found affordable at your local craft store or even Wal-mart). They come in all types of colors, but its not the color you need to worry about; simply shape into anything you want and use as a stamp.
The post includes some ideas and methods to doing this.
If you don’t want to bother making stamps, check out the sites below for bought stamps;
Lost Angels Rubberworks has some pagan themed, as well as cultures of Egyptian, Japanese, and African design.
The Third Coastrs offers tons of neat stamps to decorate pages, not just pagan themed specifically but includes myth and story themed.