Step #1: Remove Everything.
This is why it's great to clean when you're already organizing. Taking everything out makes orgaizing that much easier, anyway, and this way you can reach all of your cabinets. It's not a bad idea to grab a cloth and rub down the cans and boxes before you put them back in, as well.
Step #2: Wipe It Down.
With a warm, damp cloth, start rubbing down the shelves, including the sides. If you run into a sticky mess, a little bit of baking soda and a good scrub should get it off.
If you have shelf liner, it's not a bad idea to gently spritz with vinegar and water and let dry to disinfect the surface of your shelves so they're both clean and germ free!
Step #3: Prevent Future Spills.
You probably have things in your cabinets that spill all the time (flour and powdered sugar come to mind!). Prevent those messes by sealing those things in their own plastic containers.
Thankfully, there are a lot of affordable ways to get containers to fit almost anything, so don't be shy about using them for everything from baking ingredients to crackers and snacks.
Step #4: Clean the Outside.
Spray the outside of the cabinets with a vinegar and water mixture, then wipe away dust, fingerprints, and grime.
If you can safely get to the top of your cabinets, dust those as well. When you've finished, put down wax paper on the top of your cabinets to catch dust and make the next time you're up there a much easier task!