Hello! That sounds like an exciting trip to the historic cities of Brazil. Here are some travel tips for you.

Best Time to Visit:
The best time to visit Ouro Preto, Tiradentes and São João Del Rei is during the dry season from April to September when the weather is pleasant. The Holy Week in April is also an interesting time to visit if you want to experience unique cultural events.

Route and Accessibility:
Starting with Ouro Preto, you can fly into Belo Horizonte and either rent a car or catch a bus to Ouro Preto. From Ouro Preto, you can reach Tiradentes and São João Del Rei by road, with buses running frequently between these cities.

Accommodation and Booking:
Each city offers a variety of accommodation options. It's recommended to book your stay in advance, especially if you're visiting during peak season or during festivals. Websites like Booking.com or Airbnb are good platforms to find and book accommodation.

Clothing and Essentials:
Pack light, breathable clothes for the daytime, but do include some warm clothes for cooler evenings. Don't forget a comfortable pair of walking shoes, as you'll be doing a lot of walking. A hat, sunglasses and sunscreen are also recommended.

Health and Safety:
It's generally safe to travel in these cities, but like any tourist destinations, it's wise to keep an eye on your belongings and avoid less crowded areas at night. Make sure to take out travel insurance for any health emergencies.

Local Etiquette and Respect:
Brazilians are friendly people but respect for historical monuments is appreciated. Do not litter around the landmarks. It's also a good practice to learn a few basic phrases in Portuguese, as English might not be widely spoken.