Absolutely, I am pleased to provide some travel advice for your trip to Cusco, Arequipa, and Ica in Peru.

Best Time to Visit:
A trip to Cusco and Arequipa can be enjoyed throughout the year, although May to September offers drier, sunnier weather that's ideal for outdoor activities. However, for a visit to Ica and its surrounding desert region, the months from June to August are the coldest but are also the least humid, making them an attractive time for visitation.

Route and Accessibility:
Lima serves as the primary international gateway to Peru. From here, you can take domestic flights or buses to reach Cusco, Arequipa, and Ica.

Altitude and Acclimatization:
Cusco is situated at a high altitude (3,399 meters). It's advisable to acclimatize for a day or two before heading to higher altitudes or undertaking strenuous activities. Arequipa, despite being surrounded by volcanoes, is at lower altitude (2,335 meters) and does not typically require acclimatization. Ica, on the other hand, is at sea level.

Accommodation and Booking:
Accommodations in Peru, ranging from budget to luxury, should be booked in advance. During high tourist season, prices can surge and spaces can become scarce.

Clothing and Essentials:
Pack clothing that can be layered, as temperatures can vary significantly. For the colder highlands near Cusco and Arequipa, warm clothing, proper hiking shoes, and a rain jacket are essentials. In Ica, you will need lighter clothing, a hat, sunglasses, and sunscreen due to the desert heat.

Health and Safety:
Please consider discussing travel vaccinations with your doctor prior to your trip. Stay hydrated, especially in the highland areas, to reduce potential effects of altitude sickness.

Local Etiquette and Respect:
Show respect to the local customs and traditions. Avoid photographing locals without their permission. As with any destination, it's always good manners to offer a few words in the local language, even if it's only a basic "Hello" or "Thank you."

Have a safe and enjoyable journey!