Foam RPG skylines

OK, I made my skyline diffusers and now must cross another bridge.What to paint them with.They are blue styro foam,that two inch stuff.I have to cover about 43 square ft. I'm sure this will require a spray gun and a warm summer day so we have some time.
My foam RPG panels did best with common latex house paint. Anything that comes in a spray can with the “rattling ball” attacks the foam and dissolves it.

Latex paint can be mixed any color and available in flat and semi gloss. I used flat and matched my wall color.

After my room reconstruction they got built into the walls behind my speakers. They are hidden now by the acoustical (cloth) wall covering. However, the paint worked wonders when the RPG’s were exposed. In low light they became pretty much invisible.
My room is dedicated so appearence isn't an issue. My diffusers are skyline type and for some crazy reason they look kinda cool.Thank you much as I have a gallon of grey left over from the initial painting.These cover the back wall and still have some side walls that need something.Not sure what to do.The front wall has acoustic panels to absorb so the back sides will need to diffuse.
Tell us about how you made them. I had thought of doing the same. Did you use a hot wire cutter, table saw, or ?? what type of glue? what lengths of pieces?

I used an electrical wire made by woodland scenics.I had to make extentions because the electrodes were not long enough.I used blue styro foan from a local hardware.It was two inches thick and 4'x8'.Just make a jig saw pattern.Random is better.You can do a 4'x4' rpg skyline for about 25.00.