Sure, here are some travel tips for your visit to Panama City, Gamboa, and Colón:

Best Time to Visit:
The best time to visit Panama is during the dry season from mid-December to April. You'll enjoy sunny days and less rain during this time.

Route and Accessibility:
Panama City, Gamboa, and Colón are all easily accessible. From Panama City, you can take a direct bus to Colón. From Colón, you can take a taxi or a bus to Gamboa.

Altitude and Acclimatization:
As these locations are at sea level, there's no need for altitude acclimatization. But do remember to stay hydrated and protect yourself from sunburn.

Accommodation and Booking:
There's a wide range of accommodations for all budgets in Panama City. However, in Gamboa and Colón, options might be limited, so booking in advance is advised.

Clothing and Essentials:
Carry light, cotton clothes for the humidity and heat, but include a light jacket or sweater for air-conditioned places. Don't forget the sunscreen, a hat or cap, good walking shoes, and insect repellent.

Health and Safety:
Be careful of heatstroke, stay hydrated, and avoid barefoot walking due to potential parasites. Vaccinations against Hepatitis A and typhoid are recommended.

Local Etiquette and Respect:
Panamanians are generally relaxed and friendly. Spanish is the official language, so learning a few basic phrases will be helpful. Remember to ask for permission before taking pictures of local people, their houses, or their children.