Because of the bias edges and the lack of straight sides, this piece is going to want to shift around unless it is basted through all 3 layers. Since it doesn't appear to be very large, I would probably hand baste pretty heavily (with thread) before putting it on the longarm. I don't have any experience with spray basting, so I can't say that it wouldn't work just as well, but I would prefer to have all 3 layers firmly attached to one another before doing any intricate stitching.