Need recommendation on trowel size

I am installing 2" x 8" glass subway tiles (so a little thicker than your typical subway tile) on a shower wall. Any recommendation on trowel size? Looking around online it seemed like 1/4" x 1/4" square notch but that seemed a little big to me. Not sure if that was for 8" square tiles or for something smaller like what I am using.

Thanks.

Need recommendation on trowel size