① try to avoid the straight corner of the milling movement; corner with a helix feed cutting, to keep the cutting load smooth. ② try to avoid the workpiece outside the infeed and retreat movement, directly from the contour into the next depth. But the use of oblique progressive feed cut or spiral cut. ③ Constant feed per blade, feed the plane in a helix or cycloid path, and keep the cutting. Hole processing using milling high-speed feed to complete, not only can improve the surface quality, and can extend the tool life. ④ contour processing to keep in the horizontal plane (contour line), each layer into the same depth. When you enter the next depth, the progressive feed cuts. ⑤ processing slot and other smaller size, the choice of diameter smaller than the shape of the size of the tool to helix or cycloid path feed, to keep cutting.