Rent a car in Cancun. There are many rental agencies available. A U.S. driver's license is valid for driving in Mexico.
Go towards the airport from the hotel district. Follow the signs to the airport.
Take Highway 307 south from the airport. This highway will take you directly to Tulum. It will be about a 2-hour drive.
Follow the signs to the Mayan ruins once you get to Tulum. Pay the small fee to enter the site, and find a parking spot.
Use the map you were given to plan your day. Be sure to visit the Great Temple Castle overlooking the ocean. The Great Palace is another site to visit.
Experience the view from the tall cliffs that lead down to the ocean from the ruins, and enjoy the cool breeze coming off the ocean.
Enjoy the local cuisine and markets. Great deals are available on local handmade items. Small stands with merchandise will be scattered throughout the area.