You have to use DPNs for this, although I suppose you could do it with the Magic Loop method (but I like DPNs better). These little guys are knit seamlessly in the round, and I don't know how you could do that on a pair of straight needles.
- On a size 7 Double Pointed Needle (or one or two sizes smaller than you usually use for your choice yarn) cast on 16 stitches. I used the long tail cast on, but I think any one would work, and there are probably several different ways to do it.
- Place those stitches on two dpns. The first stitch goes on one needle, then the second stitch goes on the second needle, then the third stitch goes on the first needle, and the fourth stitch on the second needle and so on, till you have 8 stitches on each needle. Alternately, if you have some kind of figure 8 cast on or somesuch that you use for knitting toe-up socks, that would work too.
- Knit around once, putting 4 stitches on each of four needles.
- You could use a stitch marker to mark the beginning of the round, but the yarn tail from the cast on is the only thing you really need to be able to see. Once you've worked back around to it, you know you have completed a round!
- On the second round, increase once at the beginning of the first needle (I do m1l and then k4, but you could do kfb or another increase you like). For the second needle the increase goes at the end (k4, m1r). On the third needle, the increase goes first again, and on the fourth needle, it goes last.
- After every round of increases, knit one round without any increases.
- Repeat this process till there are 8 stitches on each needle. Make sure to do a round of plain knitting after the round where you increase to 8 stitches per needle.
- Start decreasing. ssk, k6 on the first needle, k6, k2tog on the second and so on around.
- Knit one round plain after each decrease round.
- When you get back down to 4 stitches on each needle (the last round you knit should be plain, with no decreases) you are ready to stuff your puff. I use poly-fill, but you could use yarn scraps or cut up t-shirts or whatever you have lying around, although I cannot recommend using dryer lint, because it comes right out when you wash it the first time.
- Put the stitches from needles 1 and 2 onto one needle, and put the stitches from needles 3 and 4 on another needle. Now you should have two parallel dpns with your live stitches all ready to finish off. I use the kitchener stitch to sew up, but you could do a 3 needle bind off if you don't like grafting. However, I thing the grafted edge looks super sweet and it is a really good way to learn the skill, doing it over and over again on tons of little puffs.
I don't have enough puffs to start joining them together, but when I do you'll hear about it.