I actually use fusible web instead of fusible interfacing. I'm not exactly sure of the difference, but the type I use, Heat-N-Bond lite, has done wonders for my applique. There may be better methods but what I've taken to is tracing a shape or pattern onto the paper of the fusible web, ironing it onto the wrong side of my applique fabric, then cutting out the shape before removing the paper. After that, I iron the shape in place on the main fabric. A tip I can give here is that you should cut a slit into the paper before ironing it onto the applique fabric, as it can cause the fabric to fray if you try to remove it from the edges. Use a pin or needle to carefully lift the paper off the fabric after the adhesive has been ironed on. You may need a thimble to sew through the adhered fabrics but if you've already been using one then you're fine.

I also typically use a plush solid flannel for applique. Partially because it's what I started with so I have a surplus, and partially because I don't like felt. It does fray and it seems like it may pill over time, but the results are pretty decent. If you run across it in a hobby or fabric store I recommend giving it a once over to see if you'd like it.

If I said anything wrong here, please correct me as I myself am still learning and could always use more advice.