Worked in the round

Turkish cast on 20 (which is 40 sts)

Inc until 32 sts on each needle (6 rounds)
Knit straight until I reached the turn of the top corners.

Decrease until 18 sts on each needle (6 rounds)

The pattern had no mention of what size the water bottle was so I had to make up my own stitch count as mine was smaller.

Also, the yarn I used wasn’t worsted even though label said it was. It was sport at best.