This pattern is approximate, as I usually improvise octopods. They are just blobs with eyes!
You can also check out a video of this process.
Use a J-size hook and wool or merino that can felt (not superwash), in worsted or aran weight. I’ve gotten the best machine-felting results with Malabrigo Merino Worsted or Manos del Uruguay Maxima. Cascade 220 works decently, although it sometimes needs more time in the washer for complete felting. I do not recommend Noro Kureyon.
For body of octopus:
R1: Ch2, slip stitch, forming a round.
R2: SC 6 (stitching 3 times into each stitch from the first round), slip stitch.
R3: SC 12 (stitching 2 times into each stitch from the second round), slip stitch.
R4: SC 18 (alternating between stitching once and stitching twice into each stitch), slip stitch.
R5: SC 24-ish, slip stitch.
Decrease (every other stitch) until 15 stitches remain.
For each tentacle:
Hooking two stitches at once, chain 11, then slip stitch into beginning of chain to form loop.
SC sides of loop together with 5 stitches to end of tentacle, turn and SC 4 stitches again to body of octopus.
After forming 8 tentacles:
Stuff octopus body loosely with chain stitch.
Decrease in rounds to center of the bottom of the octopod. Tie off.
To full the octopod:
Machine wash on heavy duty, using hot water and a small amount of laundry detergent, along with a pair of jeans for friction. Remove from machine and massage into shape, aggressively if need be. Let dry overnight.
Stitch on beads for eyes. If making octopods for children under 3 years old, embroider eyes with thread.
If you like, check out Your Daily Octopod on Twitter.