Sure! Here are some travel tips for your visit to Mérida, Barinas, Caracas -

Best Time to Visit:
The best time to visit is from December to April as it is the dry season. Try to avoid the rainy season (May to October).

Route and Accessibility:
Caracas has an international airport(Caracas Simon Bolivar International Airport), which makes it easier to access from different parts of the world. Barinas and Mérida can be reached by road or air from Caracas. They have their airports (Barinas Airport and Alberto Carnevalli Airport) serving domestic flights.

Altitude and Acclimatization:
Caracas is at a lower altitude, around 900 meters, hence, altitude sickness isn't a concern.
Mérida is at a higher altitude, around 1500 meters, but the risk of altitude sickness is still low. However, if you plan to take the cable car ride to Pico Espejo at 4765 meters, you should acclimatize yourself.

Accommodation and Booking:
In all three cities, you will find options from budget stays to high-end hotels. It is always advisable to book accommodation in advance.

Clothing and Essentials:
Venezuela has a tropical climate so light, breathable clothing is ideal. However, nights can get cold in Mérida due to high altitude, so bringing a light jacket or sweater is advised.

Health and Safety:
Ensure you are updated with your vaccinations. Also, drink bottled or filtered water only. The cities have some crime issues, especially Caracas, so maintain awareness of your surroundings, keep your belongings secure, and avoid isolated areas, especially at night.

Local Etiquette and Respect:
Venezuelans are warm and friendly people. Respect the local culture and customs. Spanish is the official language, so knowing a few phrases can be helpful and appreciated. In Caracas, more people understand English, but in Mérida and Barinas, you might face some language barriers.