Simply lay them both horizontally, with the balls on either end (not the center), and loop them through each other. Pull tight, and you have an extended bungee.
50PCS White Ball Bungee Cords, 6 Inch Heavy Duty Outdoor Bungee Cord 6 inch
50PCS White Ball Bungee Cords Heavy Duty Outdoor Bungee Cord with 12 Inch
Kesote 50pcs Mini Cream White Roses Artificial Flowers Bulk, 1.6" Small Silk
