I went to my LYS - Westport Yarns - last month and bought the yarn with the suggested pattern Mom's Cabled Mitts by Jessica Jensen. After a false start last month, I started over again this week. I was nearly finished, but the mitt wasn't tall enough for my women's extra large hands.
Normally, I would pull out my handy kitchen scale at this point and weigh the right mitt and weigh the remaining yarn and see if I had enough to make them a little longer. Unfortunately, my scale is on the fritz (Read that to mean that it's time to change the batteries and I can't figure out how to open the battery pack). So instead, I'm doing this the old fashioned way. I put the nearly finished mitt on a spare set of needles and went back to the skein, and cast on for the left mitt from the opposite end of the skein.
And I'm being extra careful to count meticulously so that the mitts match. And I actually remembered to place the thumb on the left side for the left mitt so I won't be stuck with two right handed mitts.
Stay tuned to see how this old-fashioned method of yarn usage works.