How to replicate this paint effect

I am coming to the end of my Stargate chevron project and I need to think about painting it.

By andy19422 at 2012-06-30
This is the effect I want to match.

By andy19422 at 2012-05-11
The base colour is mid Gray with a top layer of light Gray. The effect looks similar to rag rolling maybe using rolled up cellophane. Anyone know how to do it correctly?

For more control you can just dab the rag or cellophane instead of rolling it. Just be sure to turn the rag/cellophane so there isn't a recognizable pattern. I did this to one of the walls in my house.

yep id use a plastic bag

Thanks guys, that was the only way I could think of doing it. I'll do some practising