Maybe you do this the old way, with a pen and a ruler but there is no need to. You can make a stencil in SCAL that does all the work for you, to use time after time, or even make an embossing plate from thick card to give a different look. Neither do you have to stick to rectangles or circles, add a stitch border to any shape you want. Some shapes are easier to manage than others but with a little bit of alteration you should achieve great results.
Use a glue pen with a stencil and foil the stitching, or even glitter it. Emboss then colour the stitches with markers. They don't even have to be all the same colour! Or you could use a thin ribbon or twine to actually thread the holes. Of course you could also just print it, if that is convenient.
Here is the Video on how to do it.
So have some fun playing around with it, and see what you can do!