I made two of these today. I have a yard of cotton duck cloth. Here is the second one.... It's much prettier once I learned how to use the sewing machine.
And if you don't want to make one, you can get similar ones like this one, which is made for tools like wrenches.
Ah, I see. So, that's your first project, then. Even hand sewing, it shouldn't take more than two hours to sew one up. If you're totally clueless about sewing, then you can get one of these things. https://www.amazon.com/dp/B003BS34FG/?tag=thshde-20 or even https://www.amazon.com/dp/B01MQRP6Q8/?tag=thshde-20 They're not much good for _sewing_, but they'll do a straight stitch, which is all you need for basic hemming and making a case. Basically, you fold the edge over, stitch down the fold. That gives you a 'towel' looking thing, with a folded hem/edge. Then fold it upwards, stitch the sides, and stitch along the length of the fold to make the pockets. Done.