One of the most attractive features of an electric rotary razor is that you don't have to replace the blades nearly as often as a manual razor. However, after many uses the blades become dull and do not cut nearly as well as they used to. Instead of purchasing a replacement set of rotary blades, use a sharpener to extend the life of your blades. Rotary razor sharpeners are commonly available at health and beauty stores.

Detach the head of the razor from the body. This is typically done by pressing a button that releases the head. Consult your razor's manual for the process specific to your razor.

Clean the head of the razor with the small brush that came with it. If it did not come with a brush, use an old toothbrush. Remove all the hair that is caught in the head.

Remove each of the three individual rotary blades from the head casing. Use a small Phillips-head or flat-head screwdriver to remove a plate if there is one holding the blades in place.

Remove the shaving screen from each blade and replace it with the sharpening heads included in your sharpener kit. Replace the blades into the head assembly and reattach the head to the body of the razor.

Turn on your electric razor and allow it to run for five to 10 seconds. Turn off the razor and remove the head assembly from the body.

Repeat steps 3 and 4, but replace the sharpening heads with the original shaving screen.