Cleaning your oven is something that you want to do at least once a month. But any time you see a spill in there you want to make sure that once the oven is dry you go in and wipe down the spill. The best way to prevent this is to use a little bit of aluminum foil on the bottom rack while you’re cooking on the top rack and then you can just pull that aluminum foil out and replace it with something new. When you go to actually clean your oven you’re going to want to use an oven cleaner and spray it in and let it sit for a couple of hours. That’s going to make it so that when you come back you can easily scrub off the nasty grease that’s been baked into the oven. If you have a self clean oven, most of the time it comes with directions. You’re going to put it in self clean mode and let is self clean for two to three hours depending on what your oven says. You do want to make sure that you open up all your windows and doors because it does tend to smoke and make the house really smoky and nasty.