You can find this pattern free on my blog.
This pattern uses American Standard Terms.
The chains at the beginning of each row do not count as a stitch.
I am a tight crocheter so be sure to use measurements or gauge swatch.
You can adjust this pattern to fit any size water bottle by measuring the diameter of the bottom of your water bottle and working the increase rounds until you reach the diameter or just over it. For example, the bottom of my 16.9 oz water bottle is 2 inches in diameter and I increased until my diameter was 2.25 inches (Round 6 in the pattern).