To make the cowl colourful use a thread with different colours. The cowl should be easy to put and remove over the head, and remember it will stretch a little. So the length can be adjusted.
It is easy to make this cowl, chain 45 and single crotchet every line to measure 26". Then attach the sides together.
This can be done the same way knitting and then attach the short sides together by stitching with a needle or crotchet.