You will need 4-6 colors if you want multicolored.
Pick your colors of yarn and cut to fit wrist.
Tie a knot on one end and separate your colors.
Keep 2 strands in the middle to work around. Measure to your wrist or desired length and tie a knot.
I started on the left. Take your strands under the middle strands and thru the 2 strands on the right. You can start on either side.
Take the strand on top of the right and go under the middle strands and between the 2 on the left and over the top. Same as step 4.
Continue alternating strands till you get to the end, where the knot is.
Once you get to the end, tie your strands together in a knot.
You can also tie the ends together for the finish or you can put it on a buckle.