To begin, make a flat round peyote piece using a 6 bead base that covers the widest flat section of one side of your rock without overlapping. Then make a second piece that fits the width of the other side of the rock. If your rock is fairly regular you can make them both the same, if it isn't then you may have to make it larger or smaller to fit. Using the same design on both sides will make it easier for you to line up the pieces later.