As CaptainHIT said, you need VisualPrefs and Birdie.
Birdie can be a little tricky to set up, but the results can be pure eye candy particularly when used in conjunction with VisualPrefs.
I'm looking for a suitable light/dark blue camo pattern...
VisualPrefs is very straight forward, BUT you need to be careful with any colours shared with other applications as pens can be switched without colour locking enabled. IIRC there's a palette locking utility available which overcomes this.
For best results a GFX card and fast CPU will help.