Best answer I can give is this, most of us leave it on HI because if its hot enough for a fan its usually hot enough for HI. the plug wire with the stripe is hot/positive the black is hot HI the Blue is hot MED the red is hot LOW and the white is your return/negative. step 1.make sure fan is unplugged and decide what setting you want your fan to be on permanently. step 2. remove the face of your fan exposing the blades and wiring using the five clips. step 3. cut the piece of junk garbage dump switch out of your fan leaving 6 blunted wires. step 4. use a stripper/crimper (big lots has them cheep with all the connectors and tunnels) to strip the two plug wires (one solid the other striped) and the white fan wire, then the respective hot. step 5. connect the striped plug wire to the hot, the solid plug wire to the white, and separately cover the other two hot wires to prevent tangling and electrical hazards. lastly secure ALL wires away from fan blades and replace face, and enjoy your fan again.

Wires should be color coded. You can go to the hardware store and pick up some crimp connectors