The free pattern page shows this square crocheted all in one solid color. As an alternate way to crochet the square, I made this one in two colors, using that same pattern. By crocheting two rows of each color, it's possible to carry the unused yarn strands along the right-hand side of the square and crochet over those unused strands when doing the outside round, making less ends to weave in.
In the example, I used Red Heart Super Saver worsted weight yarn in a multicolor named Pinata and a solid color named Dark Sage.