You will need.
some various screws and washers
2 pliers (I used pliers and channel locks, just what I had near my desk.
Drill and drillbit
Ok, you will need about 20 minutes to make it, and 10 to install it.
Step 1: Get your stuff and start bending
Then find a style of holder you like on the internet, I chose this one. (see photo
Step 2: Done bending?
Test it first, bottle should fit. I also tested mine with a clean canteen (metal water bottle) that's a bit different shape. Took a while to get a shape that worked for both. Use your tape to tape the ends together