This is my improvement of Jeny Staiman’s Interlock Bind-off for 1x1 ribbing. My version imitates the appearance of long-tail tubular cast-on and was born because I’ve messed up original instructions.

Work required number of rownds in 1x1 ribbing, then work 2 rownds in double knitting technique: Rownd 1: *Knit 1, slip 1 wyif, repeat from * across; Round 2: * Slip 1 wyib, purl 1, repeat from * across; OR Row 2: as Row 1. For the sake of demonstration these 2 rows were omitted. Now, with a crochet hook one size smaller than your needles work a chain of as many stitches as you have on needles. (Of course, you may make only 10 chains and estimate the rest.) Cut the yarn after end of chain and undo it, then thread the blunt sewing needle with this tail. For the sake of demonstration blue yarn is used as such a tail.

Step 1. Knit next stitch as usual: you have made the first knit loop of the bind-off rownd. In case of in-the-round knitting it will be completed at Step 4.

Step 2. Insert sewing needle into next purl stitch from RS to WS, then into previous knit loop from RS to WS (may look more like from top down), return through the same purl stitch from WS to RS and slip it off the needle = you have bound off purl stitch and created purl loop.

Step 3. Insert sewing needle into next knit stitch from WS to RS, then into previous purl loop from WS to RS (may look more like from top down), return through the same knit stitch from RS to WS and slip it off the needle = you have bound off knit stitch and created knit loop.

Bound-off stitches may come out lumpy and wonky, so tighten them manually after each 10 or so stitches.

Step 4. For in-the-round knitting only. Repeat steps 2-3 until last purl stitch and first knit loop. (I accidentally my first loop off the needle, sorry for irrelevant photo!) Insert sewing needle into last purl stitch from RS to WS, then into previous knit loop from RS to WS (may look more like from top down) and first knit loop from WS to RS (may look more like from bottom up), return through the same purl stitch from WS to RS and slip it off the needle.

Done! Move the tail to WS being careful not to ruin last purl loop.

Finished bind-off looks like long-tail tubular cast-on!