....For flapping, and it being fabric, you could well get away with just crumpling it up dry. If not, just slightly dampen the flag with a little well watered down PVA. Gently roll the flag up then open it out to the required shape. 'Bend' the flag around a cocktail stick or similar to avoid any creases. To furl it, once you have rigged the flag to a lanyard , just tie a suitable length of cotton or similar around the whole thing.