Outline cookies with full strength black royal icing. Let dry. Flow in with thinned white royal icing in a cut decorating bag. Working quickly, and working on only one letter at a time, use thinned black icing and tip 1 to pipe in 2 thin concentric ovals inside the "O". Using a toothpick, drag through the icing from the edge to the center. For the next spoke of the web drag from the center to the edge. Alternate directions until the web is complete. Flow thinned white icing into the "B" and let dry overnight. Pipe black spider bodies with dots of thinned black color flow Icing. Let dry. Pipe spider threads with black royal icing and tip 1. Add spider legs and heads using black royal icing and tip 1.