I've got two of these to mount. they are muslin or cotton of some sort (likely old bedsheets). we're stitching them to stretched linen. one of them is roughly 40x50; the other is roughly 80x40. they will not be framed; there will be no glazing. I've stretched the linen. the question before us all is this: do I (and by "I" I mean "anyone other than me") use a running stich around the perimeter, or do we place a few stitches across the top and one partway down each side?