A Celtic knot pattern $4\times4$ looks like this. You can see how it is built up on a grid.
A Celtic knot pattern $8\times8$ looks like this on a grid.
A Celtic knot pattern $6\times6$ looks like this.
Can you build it up? There is a copy of the design to download here.
You can do it by making a set of cards to use on a $6\times6$ grid in a $24$ cm square with four copies of this sheet. There is also a second page with two copies of the design.
Or you could try doing it using this interactivity.
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