Here is a small tutorial on how to make faction symbols ala stephan
1. Open gimp (or photoshop, i dont own photoshop but i think it works the same) and cut out a circle.
2. Give the circle a main colour (eg blue) and paint the the top white and the bottom black.
3. Now choose 2 colours, one between white and your main calour(blue) and one betwenn black and your main colour and paint two lines.
4.+5. Take the marked tool (dont know what it is called in english) and smudge the colours so long untill you are happy with the result.
At first this will take a long time, but dont worry, with a little practice you'll get good results very soon.
6. Add details and you have a new shield ala stephan
here are a few examples how it could look like
Spoiler Alert, click show to read: