On a cutting board, lay 4 pieces of bread; place 1 slice of cheese on each piece of bread; place ¼ of the ham on the top of each piece of cheese.
Take 4 more slices of bread and spread about ½ tbsp. of mayonnaise on one side.
Place the mayonnaise side down on top of the ham; spread another ½ tbsp. of mayonnaise on the opposite side of the bread; repeat with the 3 remaining sandwiches.
Next, place ¼ of the turkey on top of each sandwich; top with another slice of cheese.
Place the last 4 slices of bread on top of each sandwich.
Press down on each sandwich firmly to press together slightly.