I adore this shawl and the pattern is so easy to follow. I found the pattern HERE however, all you need to know is on the two drawn diagrams.
Key:
. - Chain
T - Double Crochet
O - Puff stitch ( Just search for tutorials on youtube if you don't know how to do a puff stitch)
Work this pattern for half of the shawl:
Once you get to your desired length (you will have half of your shawl done). Start to decrease with the pattern below: