Its easy with the kit. Just bought one off ebay for $9.95 + S/H. I bought two filters and the kit for $98. The cleaning instructions have six steps:

1. Pre-Clean (shake and brush loose dirt off)
2. Spray on cleaner. Can soak as well.
3. Rinse off with low pressure water.
4. Air Dry. Do not use other drying methods.
5. Oil.
6. Inspect. Let sit for 20 min. Remove oil from gasket or sealing surface. Yea, I know step 6 is really like 3 steps, ut thats how K&N typed it.

 

I agree with those steps listed above, but would like to add that you can also use Simple Green to clean the filter. And oil lightly.