1. Early Start: To make the most of your day, it's advisable to start early in the morning. Arusha National Park is located near the town of Arusha, making it convenient for a day trip.

2. Game Drive: The park is home to a variety of wildlife, including giraffes, buffaloes, zebras, various antelope species, and more. While it might not have the large predators like lions and elephants that other parks have, it offers a unique opportunity to see diverse animals in a picturesque setting.

3. Bird Watching: Arusha National Park is known for its rich birdlife, including flamingos and waterfowl at Momella Lakes. Bird enthusiasts will have a great time spotting and identifying different bird species.

4. Mount Meru Views: As you explore the park, you'll have stunning views of Mount Meru, the second-highest peak in Tanzania. The mountain's slopes and forests are part of the park's landscape.

5. Canoeing (Optional): Depending on your interests and available time, you might have the option to go canoeing on one of the Momella Lakes. This activity offers a unique perspective of the park's scenery and wildlife.

6. Lunch Break: Most day trips to the park include a packed lunch, which you can enjoy at a designated picnic area while surrounded by nature.

7. Guided Tour: Having a knowledgeable guide can enhance your experience by providing insights into the park's ecosystems, wildlife behaviors, and local conservation efforts.

8. Nature Walks: Arusha National Park also offers opportunities for guided nature walks. These walks can provide a closer look at the park's flora and fauna and allow you to explore areas that are not accessible by vehicles.

9. Departure: After a full day of exploration, you'll head back to Arusha or your starting point.

Keep in mind that park regulations, tour offerings, and conditions can change, so it's important to check with local tour operators or guides for the most up-to-date information before planning your one-day trip to Arusha National Park.