Nurgle Angels: Rust shemes

So I missed a few moments with the Bolter and Chainsword Space Marine Painter.

I made up this for my Priests:

 

The legs being rusty because the travel like hell to get enough blood and gene seed!

The rest of the armor I got the advice from someone at my local game store to do it red/Black.

For the Sanguairy Guard I would like to test this on them:

Getting from this tutorial. So what to do?