i d say smalls are out the width of a 30 cm ruler (holding my hands up in the air and measuring with my eye
) and the length a bit longer. I would do whats called the 'boy fold', have the prefold so that the lines are vertical, fold a bit up at the bottom and then fold each side in tucking them inside each other iyswim. then fan out the top bit. I then would put a fleece liner in the middle and nippy onto baby or lie in a wrap and put on baby/child.
I m not sure if thats the best description
Once folded up I always thought they look about the same size as a small fitted.