There is no best way. I PREFER turn under and hand stitched. If you machine wash your quilts, I think you are best off with a machine applique of some kind - whether you do turn under or use a fusible of some kind doesn't really matter. My very first machine applique were some bears (Quiltmaker). They weren't very good. I didn't know about putting something underneath and got a lot of tunneling. but eventually, I got over it, matched them with some plain squares, made a baby quilt and gave it away. The 'baby' still has it and loves it despite its imperfections.