Certainly! Traveling to Sydney, Adelaide, and Perth in Australia can be an amazing experience. Here are some tips for your journey:

Best Time to Visit:
The best time to visit Sydney is from September to November and from March to May as these are moderate temperatures. Adelaide is best visited during Autumn (March to May) and Spring (September to November). Perth is known for its sunny weather, and the best time to visit would be from September to November.

Route and Accessibility:
All three cities are well-connected by flights from different parts of the world. Internal transport includes domestic flights, trains, buses, and ferries. Renting a car is also a great way to explore these cities.

Altitude and Acclimatization:
The cities are at sea level so there's no need to worry about altitude acclimatization. However, if you're planning on taking part in any water sports, take it slow until you get used to the water temperatures.

Accommodation and Booking:
Australia has a range of accommodations to suit all budgets, from hostels to luxury resorts. Due to high demand, it's advisable to book your accommodations in advance, especially during peak seasons.

Clothing and Essentials:
Clothing would largely depend on the season during which you're visiting Australia; generally, clothes that can be layered are advised. Don't forget to pack sunscreen, a hat, and a good pair of walking shoes.

Health and Safety:
Australia is a safe country, but it's important to take general travel precautions. If you're planning to explore the wildlife areas or outback, be sure to get information about potential hazards and safety measures.

Local Etiquette and Respect:
Australians are generally casual and informal. However, it's important to respect their cultural norms just like any other place. Littering is frowned upon and in some areas can earn you a heavy penalty. Be respectful of all wildlife and maintain a safe distance.