For my make this term I used a relatively heavy weight chest canvas and a body canvas. I then cut and pad stitched them to melton and the body of the coat.
It wasn’t until I visited a tailors workshop that I discovered that you could buy fusible canvas. I imagine fusible canvas is much more hard wearing than normal fusibles and so for a quick make this would be appropriate. I wonder if like fusible stay tape you can just iron it on or whether it requires some stitching. I guess that would defeat the object of it being fusible but having seen the finish of pad stitch the whole chest canvas, I am definitely in favour of that method!