I'm a keen baker and am now buying silicone baking mats. However when I've realised when I am baking macarons, it looks like it is going to be quite difficult to remove the paper macaron template from under the mat. Does any professional have any tips?
Yeah, don't. Either don't use guides at all (you shouldn't need them after the third or so batch), or use good ones, like this. Macarons are difficult and fussy anyway - you don't need to add to the fussiness. Eventually, you'll either thank me or curse the very idea of those wretched cookies.
I've tried to remove paper templates from under the silpat. It's an impossible headache.
One thing that does work is to draw the little circles on parchment paper. You can pipe the macarons directly on the paper, or if your silpat is transparent enough, you can just leave the paper under the silpat. I've done both of those things with some success, so it is with experience that I recommend you don't.
Caveat: If you draw little circles on parchment paper to help you pipe your macarons, flip the paper so that you pipe on the non-drawn side. Unfortunately, I speak from experience here. I used a Sharpie to draw perfect circles for my These Will Be Perfect macarons. They were perfect, except for the damn lines that baked in, transferred from the paper.
Why repeat yourself? Use a template for accuracy but make it reusable.
Use cardstock (can also be called a lot of different names, depending on where you live and whether you're at an art supply store). Personally I prefer Strathmore Bristol (https://www.dickblick.com/products/strathmore-300-series-bristol-board-pads/)
Tape your paper template (printed and tiled from a laser printer), or draw or trace the desired shapes, onto the stock.
Make sure the underside of the silicone mat and the sheet pan are dry or else the template will be difficult to pull out.
I've made tens of thousands of macarons professionally and this has been a lifesaver. I kept 5-6 templates at a time for various shapes/applications and they would each last months before needing replacing.
This technique is also great for éclairs, Paris-Brest and other pâte à choux production.