Select two identical two-door file cabinets, both made from wood. These will hold up the opposing ends of the countertop. Use colored metal cabinets to add color to your design if you prefer not to use wood.
Order an 8-foot section of countertop, with trim to match the material in the file cabinets. For example, if you add wood trim around the edge of the countertop it will give the desk a finished look. Select a counter material that compliments the file cabinet material.
Set the countertop atop the file cabinets. Move the file cabinets so that each one is holding up an opposing end of the desktop. It is not necessary to secure the desktop to the file cabinets, as the countertop is heavy. By not affixing the top to the cabinets with liquid nail, the desk is easier to move, if necessary.