This is how it looks without the cover.
I used old recycled 100% woollen Swedish army fabric. I draw the pattern by using the bottle itself as a guidance.
I made the lining too. The cover needs to be thick to avoid burns and keep the water hot as long as possible.
I didn't draw paper pattern but used all the time the bottle to "stay on map".
This bottle is not big. Only my hand fits well in.
I closed the bottom by using velcro.
Also this is my very own design. Information about it also at On Tour site.