Instead of stitching templates I use tracing paper... you can buy it in pads. I either freehand or trace the design I want onto the tracing paper holding it over the layout so that I can get an idea of placement and size. This is helpful because you can see through the tracing paper which makes freehanding a lot easier without having to do anything to the layout yet.

Next, if it's easier I cut out the "template" leaving an edge around it about 1/4 of an inch. Then I turn the tracing paper over and put a thin layer of restickable stick glue on it and give it about a minute to dry partially. Make sure that you put the glue on the tracing paper and not the layout otherwise the glue will simply stay on your layout.

After about a minute when the glue isn't quite so tacky I place it on my layout where i want it and smoothly press it down. The restickable glue will stay on the tracing paper but will keep it from sliding around or moving while you're stitching.

Next I use a paper piercer to pierce holes evenly across the template lines. Depending on how long you want your stitches depends on how far apart your holes will be. I find it easier to pierce the paper if I set it on top of a sturdy and empty cardboard box. That way I can just pierce completely through quickly and easily.

After you're done piercing the holes you can start stitching making sure your stitches aren't loose. Once finished simply pull the tracing paper off, generally it will tear off in sections since it is perforated from stitching over it.

If you have a simple pattern you can go ahead and peel off the tracing paper BEFORE you stitch, that way you have it to place the holes with the paper piercer and then you can just follow the piercing holes as a template.

Hope this is helpful and I've included a photo of a layout I was stitching on with the tracing paper as a template. You can see the completed layout in my gallery.