They are worked in the round. You can use dpns or a circular needle and magic loop.

I used Filitaly-Lab Manta, a yarn I love, but you can substitute it with any worsted weight or aran yarn of your choice. Onda su onda wavy stitch is very stretchy.

These mitts are perfect with Onda su onda hat and neckwarmer. I thought them for a man, but they suit women too.

Thanks to my skilled and supportive testers:
Accordionmama
Cazantal
haexe
SAD
Suniru
whistlesandbells

6/10/2010 lo schema è disponibile anche nella versione in italiano!

01/30/2013
A comment from a knitter, failbetter, it may be hepful for many others:
1) It took me some time to figure out that in fact one should knit the chart twice per round. It’s not obvious since mittens often are knitted plain on the palm side.
2) The instructions for placing the markers for thumb gusset increases are for knitting on circulars and don’t work for knitting on dpns where the markers would fall off. For dpns where the second pattern repeat ends on the end of the fourth needle, here’s what I did: I knit without a marker until gusset increases, then at the first round of gusset increases placed a marker where the pattern ends. The gusset increase stitches will then accumulate between this marker and the end of the needle.