A friend of mine is a terrific beader. She makes really pretty jewelry, and she offered me a trade. She wanted handwarmers and she'd make me jewelry for them. I agreed.
We headed over to Imagiknit in San Francisco, where she picked out some lovely Abstract Fiber laceweight in the Matisse color.
However, I am incapable of really knitting with lace weight, so because the yardage was extremely generous in the skein (420 yards), I doubled up the yarn as I only needed about 210 yards per handwarmer.
I showed her some patterns on Ravelry, and she picked out the design elements she liked from a few photos. Luckily, these design elements were easy (ribbing, vertical ribbing, and some YO/k2tog lace). She wanted longer handwarmers (mid way to her elbow) with a little bit of lace at the palm.
So, I took her measurements for her arms, and sketched out the design she had requested. I made some test swatches so I could get a feel for what gauge the double strand of the yarn was going to be happy (10 stitches per 1"; 15 rows / 1.75" -- US Size 2 needles).
After I found the yarn's happy place, I cast-on. There was some re-designing on the fly to take into account my gauge, actual measurements, and where I thought elements might look good versus my initial sketched ideas.
I took copious notes for each change. There were several "fittings" along the way as she tried on fit. There were also numerous camera phone images via text message as I sent her "progress reports".
At one point when the initial 15 rows of ribbing were done, I cast on the 2nd pair of arm warmers on another set of circular US2 needles using the other end of the yarn cake. I then knit up to the 15 rows of ribbing, and then put both on 2 circular needles so I could make sure that I did all of the decreasing and design elements exactly the same.
A rough guideline for this pattern
1) I cast on 54 stitches in a 3x3 (this allowed me to fit the widest part of her forearm @ 8")
2) Knit for about 15 rounds
3) Began arm decreases (1 decrease every 3 rounds) 6x -- I made the k2tog decreases in the purl part of the 3x3 rib to "hide" the decreases. There was a total of 5.5" of ribbing.
4) Purl 3 rounds, Knit 3 rounds, Purl 3 rounds (for the next design element)
6) Knitted stockinette stitch and started the thumb gusset about 3/4" from where the wrist starts. Increased until the gusset was about 22 stitches.
7) Put the thumb stitches on a scrap yarn
8) Knit for 3 more rounds
9) Purl 1 round
10) (K2TOG, YO) for the entire round
11) Purl 1 round
12) Knit 2x2 ribbing for 3 rounds
13) cast off the hand
14) Picked up 22 stitches for the thumb,
15) Decreased the thumb by 2 stitches
16) BO with a sewn-off binding.