Sand the oak cabinets with 200-grit sandpaper. This will roughen the surface slightly and help the paint adhere to the wood.
Mix equal amounts of white vinegar and water in a small container. Apply this mixture to the cabinets with a rag to clean the cabinets and remove any greasy residue that may have accumulated over time.
Thin any color of latex paint by mixing three-parts paint and one-part water.
Brush the thinned paint onto the exterior of the cabinets with a 6-inch stain brush. The brush strokes do not have to be perfect, just cover the cabinets with paint.
Take a clean rag and wipe the wet painted cabinets from the top to the bottom. This will remove brush strokes and some of the paint so that the natural oak shows.
Repeat applying and wiping the thinned paint until you have reached the desired level of coverage.
Apply two coats of water-based polyurethane clear coat to protect the paint and give the cabinets a shiny finish.