This shawl is worked top down from the centre. This is a modified half-pi shawl, based on Elizabeth Zimmermann’s pi shawl construction. You can start with a provisional cast-on to be grafted at the end. Leave a tail of about 20cm at the start of the cast-on for grafting. If you are not comfortable with grafting, you can thread the tail from the cast-on sts, pull the yarn tight to close up those sts and weave it in.