A simple tutorial for the snap clips that I love making. Thought I'd share some of my techniques..
First: you need the snap clips, which I personally purchase from the craft stores and hair specialty stores local to my area. You can purchase them in batches from various stores on Etsy. My snap clips are 3 inches in length, but you can use any of the kinds out there. I also make use of securing the felt 'body' to the clip through the three top holes you see in the first pic. There are clips that do not have these holes, and they are probably smaller than 3 inches in length, so it won't be hard to secure the felt to the metal clip.
Second: You need the felt, and that can also be found on Etsy. Now that I've been doing this for a while, I prefer wool felt. Wool felt is thicker, but doesn't pill. But whatever felt can be used, including the craft felt.
Third: Embroidery thread, and those are also at your local craft store. I use a the whole thread and do not separate. I prefer the thread thick, but if you prefer it one thread, you can separate and use just one.
Make sure you outline the original clip, cut through 2 identical pieces and then estimate the position of the slit for the back felt piece of the clip. I usually go through all the steps you see pictured here and then I secure the whole thing before I start sewing.
Here is an illustration on a blanket stitch, but you can use any other technique : back stitch, running stitch or whatever is more comfortable. Make sure the stitches are close enough to the clip to secure it and not have it wobble.
Now for the top of the clip, I have been known to put flowers, buttons, stars and hearts. You can add anything you want. All you need is to glue it on there and you're set. And have fun with it!