Weathering with salt and hairspray. (1)

STEP 1 : find something to paint. I had this selfmade terrain piece
 laying around in a boxmade made from plasticard.

STEP 2: paint it black and ad brown for the second layer of paint.

STEP 3: Give it a rusty look. after this stage ,  use hairspray and salt. and let it dry.

STEP 4: red primer.

STEP 5: Use warm water to take the salt off and finish the job the best you can.