Buy a regular bathroom hand towel, not to thin and not to thick, a good medium texture. Lay it flat and cut it right down the center:
This will allow you to make 2 holders! Then you want to fold over and pin the raw (cut edge). I pin it and then sew a straight stitch. You may want to serge it or even bias tape it for more durability.
The next step is to fold over the bottom, where the toothbrushes slide in. I fold it in the middle of the decorative embroidery section, move it around to however you like it most. Then you will want to measure for your toothbrushes. I start in the center and work my way out, but really it just needs to fit what you want.
It helps me to actually set up the toothbrushes then measure across the bottom, while marking, this particular one I measured 1.5 inches for each section except the toothpaste in the middle was about 2 inches. I would not suggest using the large tubes of toothpaste, this one is the smaller 3.5 oz, I think the larger ones may weigh it down to much. You dont have to add toothpaste at all, I just thought I would see how it turned out.
Once you get the bottom marked, mark the top as well to help guide you while you are sewing. Next you will go to the sewing machine and sew a straight stitch along all your measurments. Then you are done. I do like to reverse stitch the tops to make them a bit stronger as that is where the tugging will be as they are pulled out.
Lastly you will either want to attach metal circle snaps, or just sew a button hole in the top corners and hang it on the wall. And you are done! It takes about 20 min to sew one and the cost is practicaly nill, If you buy a hand towel for two bucks, your cost is 1.00 a holder!!
Happy toothbrush holder making!!