The scarf is worked on needles larger than those normally used for the yarn in order to achieve an open fabric with good drape. It is knitted in two pieces for the sake of the wavy lower edge characteristic of the stitch pattern. A wider scarf or shawl could easily be made by increasing the number of repeats.
Please note that this piece will appear wider at first than it will become after a few inches of knitting: the stitch pattern will cause the fabric to draw inwards.
Version 2 -- February 17, 2010.