Cut the yarn, leaving a long tail, and pull through remaining stiches, securing in first loop. Use the remaining tail to join the sides together. If you used multiple colors, use the tails from the color change to join that color's section together. Weave in any remaining ends.
There is no regular bind off. When you get to the final stitches, you pull the yarn through them with a crochet hook or large-eyed needle and pull them tight like a purse.