from Edinburgh
The usual ladies' costume is a long white dress, down to the ground, with a tartan sash on the shoulder held on with a brooch the same type as the men use for their plaidies. The lower end is fastened at the waist on the opposite side from the shoulder it is on and the bit over the back is left hanging loose. There are all sorts of arguments which shoulder you should have the sash on but I think the right one is safest. No doubt somebody will think otherwise.