This was posted just a few days ago and I didn't bookmark it.
This technique is using cut, raw edge pieces of fabrics and placing them onto a large section of back ground fabric, probably white, and top stitching about ¼ of an inch away from the edge then placing another piece a short distance from first and stitching that in place. The edges are not tacked down.
The pieces are placed randomly but equally distanced from the previous piece. I think you start in the midle and work out!
I hope this is understandable because it is harder to explain than I thought.