Pic 67: This sail is being fitted to its stay by opening up the little brass mounting rings and closing them over the stay. The thin grey lines attached to the corners are part of the 'running rigging'. In a real ship this would be used to hoist sails up and down and partly furl them. In short, it must make mechanical sense. The line that pulls a sail up is a 'halliard', and the line that pulls a sail down is a 'downhaul'. Don't make the easy mistake of fixing the downhaul to the bottom corner - if you think about it, both lines must be fixed to the top to work!
Caution: Don't glue the running rigging in place. By all means run it through the correct hole in the pinrail to keep it tidy, but don't waste time making it perfect because it will probably have to be moved or adjusted later.