Yarn weight: fingering, sock or 4 ply.
This would work well in a Scheepjes whirl or a high twist sw merino & nylon sock yarn.
There are instructions included for making this into a mobius/infinity shawl.

This is an intermediate level pattern.
More important than gauge for this pattern is that your chain stitches are consistently the same size (length) as the width of your double crochet stitches. Chain stitches which are too long, too short or inconsistent will pull your scarf out of shape and it might not be possible to correct with blocking.

There is a small mistake on the diagram/chart: on the right side, there are two rows numbered 8! The lower one should obviously be row 7! Sorry.