First, in order to do a real quality job with your cabinets it really is best to remove all the doors and drawers. This will allow you access to areas that would be difficult to reach with the doors and drawers left in place.
Once the doors and drawers have been removed from the cabinet frame or boxes as they are sometime called, removed the hardware- hinges and handles. Now is the time to think about replacing them and giving your cabinets a completely new look, however, if your hinges and handles still look great than you’re okay.
Try to find or create a good work area to lay out your cabinet doors and drawers. You will need an area to work comfortably in and with as much ventilation as possible. Remember, since you are painting your cabinets and not staining them you don’t have to remove the existing finish unless it has failed or in a state of failing. But for the record we will assumed the worst and go from there.
Use a good cleaning solution to remove grease, grime and other oils from the cabinet surfaces. Trisodium phosphate and a host of other degreasers can be purchased at your local hardware store or home improvement center. Thoroughly clean the cabinets inside and out and allow them to dry before proceeding. Once the cabinets are clean and dry begin sanding.