Measure around the highest part of the leg where you want the sock to be. Subtract one half to one inch from that measurement. If the measurement is 14 inches, subtract an inch to make it 13. Test the gauge by knitting a swatch in the ribbing pattern with the yarn and needles you will be using. Measure the swatch to see how many stitches are in an inch. When you have determined the number of stitches per inch, multiply the stitches per inch by the measurement you took around the leg. For instance, if your gauge is 6 stitches/inch multiply by 13 inches to get 78 stitches. Since the pattern requires that the number of stitches be divisible by 3, check that. The example given is divisible by three and would give 26 stitches per needle. If the number isn’t divisible by 3, add or subtract a stitch or two until it works out.
Measure the bottom of the foot. Measure from the heel to the highest part of the leg you want to sock to come to. Add these together to get the length of the sock.
It isn’t a bad idea to check the fitting once the sock is about 6 inches long and make sure it slips over his foot okay.
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