Very clever idea! A wonderful gift, and you know it will be used by your daughter.

That's very ingenious of you! What nice colors!

For my girl scouts years ago, I made a water bottle holder. I used material from a dress my mom was throwing out and a rubber "O" ring that (when the material was sewn on both sides) would just fit over the top and rest snugly under the lip of the water bottle. I made varying lengths for the strap as some of my girl scouts were taller and others were shorter. I suppose a small pocket could be added to one strap for a cell.