Here is the step by step process I have used for many years . When finished , My skulls end up looking like a plastic model

1. Place skull in crock pot until meat falls off bone.
2. Using a garden hose, Spray meat off and inside cranium with garden hose , teeth should come out at this point.
3. Fresh water in crock pot along with good amount of liquid dish soap to degrease bone. Let cook in hot soapy water for about the same amount of time or less than step one.
4. Spray off fine pieces
5. Place skull in Hydrogen peroxide and soak till white.

Tips: Do Not Bleach as bleach will make bone Chalky
Animals such as Bobcats and raccoon are more delicate and require less cook time than a heavier boned animals such as beaver and coyote.