Step 1:

Use a lighter and burn the end of the cord and flatten it so the string inside doesn't come out.

Step 2:

Measure 8 feet of cord. (If you are doing two colors, measure 4 feet of each and burn the ends together so it is about 8 feet long, but still using the same method).

Step 3:

Get a relatively small buckle and grip the two ends together and put them through the buckle together.

Step 4:

Pull the cord through, but leave a small loop at the end to put the cord through. Once you have done that, pull it so it is tight.

Step 5:

Put the other buckle on and wrap it around your wrist leaving space.

Step 6:

It is hard to put into words so do what the photos show. What I can tell you is to, on the end going down, wrap it over and inside the "loop" you see.