I recently designed a new project that requires a "sky" fabric. I don't have a lot of blues in my stash and certainly nothing that could be used as a sky background. I thought about dyeing something, maybe going shopping but in the end decided to work with paint. I mixed a few Setacolour fabric paints.....blues, green, yellow and a pinky
orange, all of which I diluted quite a bit with water. I wet a piece of off white cotton, put on my rubber gloves and began pouring the paint here and there. I really just kind of squished it to get the colours fairly well blended.
Next I laid the piece out on some plastic sheeting raising some areas to create peaks and valleys. (top left) Sprinkled a generous amount of coarse salt and left it overnight to dry. The photos on the right show some close ups of the finished piece of fabric. I think this will work out just fine.