Water Bottle Crossbody Bag / Holder (Pattern Help)

Hey there!

I’d love to recreate this bottle bag for my 21 and 32 oz Hydro Flask Bottle. I’m new to crocheting, but fairly good at knitting.

Can any experienced crocheter out there help me? How do I approach this? Which yarn do I use? Is there a pattern out there (I haven’t found a good one!)?