I use Woodland Scenics, Scenic accents glue. It is a thick tacky glue. I roll the sail around a paint brush handle to curve it, then I apply a thin line of the glue with a toothpick to the top edge of sail. With the tackiness it sticks to the spar on the first try and allows repositioning. once it is positioned I place a small amount where the base of the sail touches the mast. I curl the sail enough so that it fits between the spar and the platform on the mast.
