This is a beautiful way to show your love and the binding of yourselves to each other on your wedding day.
Handfasting was an old way of showing the commitment that two people had to each other. They were literally bound together until the formalities of marriage could be conducted.
The materials used today are as beautiful and varied as you like. From wedding ceremony themed colours to simple cords, even football scarves or a meaningful piece of fabric.
I use silk ribbons or cords decorated with meaningful charms such as, the tree of life or a Celtic knot, symbols of love and commitment. Your binding in love can be any colour you want, or I can advise you on symbolic colouring.