Lace collar

It starts with knitting a strip of squares, as for filet crochet (double crochet, two chain stitches), and then the main pattern. The pattern repeat is equal to four squares, you need to cast on a strip that is a multiple of the repeat plus one more square for symmetry. This collar has 53 squares, it is almost up to the neck.
The rows that are drawn in red on the diagram: double crochets are knitted under the arch, single crochets are made in the third stitch of the group of four double crochets (the macro photo allows you to see the pattern by the stitches). Why the third? I selected it experimentally for symmetry reasons.

I finished the collar only along the neckline: 3 chain stitches, a single crochet in the double crochet of the first row. It could have been left unbound, I left the side edges as they are, but it seemed that the neckline would be softer this way. The ribbon is 3 mm wide, woven into the squares of the first row. For the ends of the ribbon to come out of the squares symmetrically, the number of squares must be even, so I had to skip one square in the middle of the collar (visible in the macro photo).