Using smaller needles and MC cast on 40 (44) sts and divide the stitches onto four double pointed needles (dpns), 10 (11) sts onto each. The beginning of the round will be between the fourth and the first needle. Join to work in the round and work 8 (9) cm in twisted rib stitch.
K 1 round and at the same time increase 1 st on each needle = 44 (48) sts.
Change to larger needles and start following the colourwork chart in the following way:
Women’s mitten: Start at row 1 of Chart I.
Men’s mitten: Start at row 1 of Chart II.
Work rows 2–14 (2–16) of the chart.
Note: When the colourwork strands span 5 or more stitches, weave the strands into knitting on the wrong side of the fabric.
Next, mark the position for the thumb hole:
Next row (chart row 15 (17)): Needle 1: Work 11 (12) sts in pattern; Needle 2: Work 9 (10) sts with a small length of contrasting colour yarn (see the red line in the drawing), slip the stitches just worked back onto the left needle and work them in pattern; Needles 3 & 4: work in pattern.
Women’s mitten: Work rows 16–49 in pattern. You will be decreasing 1 st on the second and fourth needle on row 40 and 1 st on each needle on rows 41–49.
Men’s mitten: Work rows 18–54 in pattern. You will be decreasing 1 st on the second and fourth needle on row 44 and 1 st on each needle on rows 45–54.
Cut yarn, thread through stiches and weave in ends.
Work as left mitten reversing the position of the thumb. The thumb hole will be worked on the third needle.
Remove the contrasting yarn marking the position of the thumb. Pick up the sts along lower and upper edge of the hole onto larger needles. Pick up stitches at each end of the hole so that you have 19 (20) sts for the thumb. Divide the sts onto three needles. Join to work in the round and work following the stitch pattern on needle 2 of the mitten.
Work in pattern until the thumb measures 5 (5.5) cm or until your thumb nail is covered up to halfway. Next, work with MC only and start decreasing for the thumb tip:
Next round: On each needle, work to last 2 sts, k2tog. (4 sts decreased.)
Repeat on every following round until you have 4 (3) sts left.
Next round: K1, pass the other sts over the knit stitch from left to right.
Weave in ends.
Steam block the mittens gently.