Here are the things you will need:
- Cotton or Nylon Webbing
- Ribbon(optional)
- Hardware set- two sliders and one D ring( I found mine Here)
- Measuring tape
- Scissors
- Sewing Machine
- Thread
Source: http://www.mysocalledcraftylife.com/2012/09/12/beau-and-rouxs-corner-diy-martingale-collar/