Fry bacon and drain or use the precooked. Combine cream cheese, swiss cheese and mayo in bowl. Then spread mixture into a square pyrex dish or something similar. Crumble sleeve of Ritz crackers and crumble crispy bacon on top. You may use only 1/2 of the bacon if you prefer. Bake at 350 until bubbly. Serve with your favorite cracker or Frito scoops.