I was proof-reading a new pattern of mine today that will soon be published by LYDIA Yarn, (!!!) and I noticed that part of my directions for this knit-in-the-round item include the following:
"Decrease one stitch when joining—slip the last cast on stitch onto the left needle and knit it together with the first cast on stitch. This will prevent the gap left when joining in the round."
So simple, yet so effective! For years, when joining in the round, I just joined, hoping for the best, and went back later and stitched that gap closed. Since I was knitting a lot of hats and cowls and pairs of socks, we're talking a lot of "hoping for the best" and going back to fix it later. This in itself isn't a bad practice. My finished items looked fine and it wasn't that big of a deal to stitch the gap while I was weaving in the tail end of the yarn.
Now that I cast on an extra stitch and knit the first together with the last, however, frankly I feel pretty clever. I like feeling clever (it's kinda rare), and I know you probably like feeling clever, too (you manage it more often than I do, I'm sure).
So here's what this looks like, this clever simple tip: