The yarn I used was 12ply so I had to use a 6.5mm hook and add an extra row per repeat to get gauge. I also had to add an extra chain and use TC to get the star to the right size (Ch 6, SC in second ch, HDC, DC, 2 x TC).
Such a cute hat and I’m a bit sad that I had to gift it! I have enough yarn to make a second one though! Just need to get more lights