Woven Applique Celtic Knots (or, WACK) are simple Celtic knots you can make using a variety of materials (paper as well as fabric) in your choice of methods (from raw edge fusible to needle turned edges).
Download and print Style E 2×3 Celtic knot template. The template looks like this.
Cut two loops (cut out the doughnut holes in the middle, too).
Cut open the loops along the dotted line.
Lay one loop on top of the other, like this.
The lines across the loops indicate where another loop crosses over it.
Arrange the two loops to look like this: