I've seen this priping done on so many different cakes, is there a template or something everyone is using or is it just a popular design with perfect piping skills?
AI'm pretty sure that is just freehand,and it looks like royal icing to me. HTH : )
that looks freehand, its easy to practice, make your design on wax paper, tape it around a large bowl and practice piping the design. it really helps, because when you are working on scrolls or designs it is ALL about the pressure on the piping bag. consistent pressure is what you are looking for. Also if working with small dots or scrolls you can add a little kayro syrup to the RI to make it more pliable and it gives it a nice sheen.
That is actually pretty basic piping, just some dots and some lines. Make up a batch of icing and start practicing. Take a cake pan and flip it upside down on some non-skid to practice. Pipe all over it, scrape it off, put it back in the bag and do it again and again. Just keep reusing the icing. It is amazing how much better you can get if you just do 15 minutes or so each day.
You can use a plastic cut cup or a round cookie cutter to lightly imprint on your cake so the garland will be all the same width and length around cake. See this video of how this chef uses these things to do garland. This way it will be even all the way around.