Before Starting

• Carlo Morelli, of Thenewhomemaker.com, recommends cleaning your existing countertop with detergent or warm ammonia and water. Let it dry, and tape off any areas that abut the edges ton which you don't want paint.
  
  

Prep the Surface

• Fill any chips or holes on the existing counter. Naturalhandyman.com recommends using two-part wood filler for this step and sanding the filled chips within 15 minutes after it has dried.
  Sand the entire countertop using 120-grit sandpaper to rough it up and allow the primer and paint to adhere more effectively.
  
  

Primer

• Apply a bonding primer/sealer to the countertop. Naturalhandyman.com suggests using a short nap roller for the smoothest application and finish results. Tinting the primer to closely match the final paint color will prevent any bleed-through of your primer color. Allow the primer to dry thoroughly, ideally for 24 hours.
  
  

Painting

• Although you can use oil- or water-based paint, Carlo Morelli warns that if you'll be preparing food directly on the surface of your painted countertop, you should use water-based paint. (Oil-based paint can leach chemicals into food but will also provide a smoother surface and will be more difficult to chip than water-based paint.)
  
  For either type of paint, apply two or three thin layers, allowing for dry time between each layer.
  
  

Final Seal

• Carlo Morelli recommends sealing the paint with three coats of polyurethane, preferably a water-based sealer in satin or high gloss. Allow the sealer to dry for 24 hours or more before placing anything on it.
  
  

Warning

• Once you decide to paint your countertop and start sanding it, you cannot change your mind.
  
  Naturalhandyman.com warns that your new painted countertop will not have the same strength and durability as your original countertop and suggests using cutting boards and hot pads and preventing any rough surfaces from sliding on your new painted counter.