Rome is very beautiful but it can became overwhelming very quickly. I would suggest to spend 3 full days in Rome to see everything. Be aware that in the most tourist area they tend to take advantage of tourist and jack up the price of food and drinks. Try to avoid restaurants that have “tourist menu” or fettuccine alfredo on the menu.
Most of the famous destination have very long lines, one way to skip the lines is to go with a tour or try to book night tours. For the Pantheon the best way to skip the line is to go there right at opening at 9am. The best place to see the Forum (in my opinion) is at night from the Campidoglio (coordinates: 41°53’33.1″N 12°29’01.0″E)
A great way to Explore a new city is using the Hop On Hop Off bus. This bus lets you take a tour of the all city with a very informative narration. You can then decide when you want to get off the bus or simply stay on and continue.
Other than the famous tourist destination (the colosseum, the forum, Sistine Chapel, Trevi fountain etc) i would suggest you to visit some lesser known area that are quite and really beautiful:
- The ghetto: this is the Jew area of Rome. During the Papal kingdom there were gates at the entrance that were closed from sunset till morning. Here you can try some of the authentic Roman Jewish food.
- Trastevere: this used to be one of the poorest area of the city, now it became a very popular destination at night for great food, bars and a walk.
- The garden of Villa Borghese. This is a great oasis of quite in Rome.
These are my 3 favourite walks in Rome 3 walks in Rome
Here a great travel guide for Rome