Fluvial by ChickenBetty is a simple 16-stitch pattern of undulating, tessellated waves which alternate with single crochet, making this pattern look more complicated than it is. It's a perfect one-skein pattern, and can be worked in almost any weight yarn with the recommended hook size.
This pattern is available as a PDF download.
Sock weight version is 28" around x 6" deep
DK/sport weight version is 35" around x 9" deep
Sock weight version is about 6.5 sts/5.5 rows = 1" in wave pattern
DK/sport weight version is about 5 sts/4 rows - 1" in wave pattern
For sock weight version: Valley Yarns Franklin Sock Yarn
(now Disc color), 1 skein, 450yds
For DK/sport weight version: Rowan Felted Tweed - Color #183, 2 skeins(382yds)
For sock weight version: US Size B/2.25mm crochet hook
For DK/sport weight version: US Size F/3.75mm crochet hook