Hello! That sounds like an exciting trip to the charming islands of Malta. Here are some travel tips for your journey.

Best Time to Visit:
The best time to visit Valletta, Mosta, and Zurrieq would be from late spring to early autumn (April to October). During this period, you can enjoy warm weather and numerous local festivals.

Route and Accessibility:
Malta International Airport is the primary international gateway into Malta. You can easily reach Valletta, Mosta, and Zurrieq via numerous transport options such as taxis, buses, or car hire. The cities are also quite walkable and have good public transportation infrastructure.

Accommodation and Booking:
All three cities have a variety of accommodations to choose from that fit different budget ranges. It's advisable to book your accommodations in advance especially during peak tourist season to ensure availability.

Clothing and Essentials:
Pack lightweight and breathable clothing for the summer months and layers for cooler evenings. Don't forget a comfortable pair of shoes for walking, a hat, sunglasses, and sunscreen to protect from the sun.

Health and Safety:
General travel health precautions apply. Ensure that your routine vaccinations are up to date. Tap water is generally safe to drink, but bottled water is also widely available. As always, ensure you have travel insurance to cover any unexpected incidents.

Local Etiquette and Respect:
Maltese people are warm and hospitable. It is respectful to greet people politely in public places. It is also important to dress modestly when visiting religious sites.