Gauge is not important.
Pattern can be done in a variety of yarn weights/hook sizes depending on how heavy or big you want it.

I used a 4.5 mm hook and 2 skeins (1000 m approx.) Lion Brand Mandala Baby (3 weight) when designing, which resulted in a shawl that was 29” (74 cm) from centre to bottom tip, and 62” (157 cm) across at top.