How to Make an Invisible Join
To join or end a round, work the last stitch and cut the yarn, leaving a 6"/15cm tail.
Step 1 Pull the tail through the loop of the last completed stitch, and thread it into a yarn needle.
Step 2 Skip the beginning chain and insert the needle under both strands of the next stitch, then pull it all the way through.
Step 3 Insert the needle into the back loop of the previous stitch and pull it through.
Step 4 Weave in the yarn end on the wrong side.