True needle turn applique is done by hand because, as stated above, it is turned under by the needle as you stitch. However, there are methods of approximating needle-turn by machine. Eleanor Burns has one method of stitching the patches to light-weight interfacing and turning the edges in by cutting a slit in the back of the facing. Another method is to use freezer paper and ironing the seam under. Both these methods call for an edge stitching by machine that is almost invisible. I think the important thing, for competition, is to be sure that the method you use looks like it is intentional and part of the design rather than a 'shortcut'. I enjoy both hand and machine applique.