This can’t get much easier, really.

You’ll need:

Yarn. Any weight. Less than 1 ball, typically.
Needles, double-points, appropriately sized to your yarn.

1. Swatch your yarn with your chosen needles. Make a 2 inch square.

2. Count how many stitches you have in one inch.

3. Measure around your baby or child’s thigh. Subtract 1/2 or 1 inch.

4. Do some math. (stitches per inch) x (inches around thigh - 1/2-1 inch for ease)
Example: My yarn gets 10 stitches per inch, and my baby’s thigh is 9 inches around. After I subtract 1/2 inch, I have 8.5 inches times 10. I get 85.)

5. Cast on the number of stitches you got in step #4. Join in the round. Of course, don’t twist your stitches.

6. Make ribbing for an inch. You can do whatever ribbing you want. k1p1, k2p1, k2p2, k3p1, whatever.

7. After that inch, you have a decision to make. You can make the body of the legwarmers in stockinette (knit every round), or you can make the body of the legwarmers in the ribbing pattern you started with.

8. If you opted to knit the body of the legwarmers in stockinette, keep knitting until your legwarmers are one inch shorter than you want them to be. Then knit another inch of ribbing.

If you opted to knit the body of the legwarmers in ribbing, keep knitting until your legwarmers are the length you want them to be.

9. Cast off. Choose one of the stretchy cast-offs here. I prefer Elizabeth Zimmerman’s sewn cast-off.

10. Make another one.

Do you crochet? Adapt this pattern to crochet by swatching in whatever crochet stitch you think would work best for your legwarmers. I don’t crochet, and I have no idea what would work, but if you DO crochet, you ought to be able to figure something out, I would think.