You will need threads or yarn and a buckle of some kind, in this example, I've used
two metal rings. You can also leave a bit of yarn in the beginning and the end, so
you can tie the belt instead of locking it .
Prepare two thread bunches with four threads in each.
Make square knots on the middle of buth of them.
Put one of the threads through both of the rings and fold the square knots you've made in half as in the picture above. Make a pair of square knots so its secured on the rings. Do the same thing with the other thread bunch.
The two bunches should now be split in four. Divide them so you get four threads in each bunch.
Make square knots of the four bunches. 5 on the outer and 3 on the inner.
Make a shared square knot with the four threads in the center.
Split them up again and make three more square knots.
Now put the threads together in two groups again. Take the four middlest threads in each group (a) and tie a square knot of these (b). Do the same to both sides.
Repeat steps 5 to 8 until you've got a belt in proper length. You might have add strings as you tie. Finish the belt with a overhand knot and leave a fringe at the end (see the first image in the tutorial).
Macrame belt tutorial