To make the most of your day in Rome, it's best to take public transportation. The metro system is efficient and easy to use, and there are plenty of buses and taxis available as well. If you have a lot of ground to cover, consider renting a bike or a scooter. Keep in mind that traffic can be heavy in some areas, so plan accordingly.
If you want to see more of Rome's highlights, consider adding an extra day or two to your trip. If you have less time, focus on one or two key attractions or neighborhoods to explore.