Because Mexico is massive, covering long distances is best done by air.

Flights: Domestic carriers like Volaris, VivaAerobus, and Aeromexico offer highly affordable, frequent flights between major hubs (CDMX, Guadalajara, Cancún, Oaxaca).
Buses: For regional travel (such as moving around the Yucatan Peninsula or from CDMX to Oaxaca), Mexico's luxury bus system is world-class. Companies like ADO or ETN offer massive reclining seats, AC, and onboard entertainment, making them incredibly comfortable for 3-to-6 hour journeys.

While credit cards are widely accepted in nice restaurants and hotels in major cities, Cash is King in Mexico. You will need physical Pesos for street food, artisan markets, taxis, and small convenience stores.

Tipping (Propina): Tipping is expected in Mexico. In restaurants, a 10% to 15% tip is standard for good service. It is also customary to leave 20-50 pesos for hotel housekeeping, and to tip the grocery store baggers (who do not receive a salary and rely purely on tips) 5-10 pesos.

Water: Do not drink the tap water anywhere in Mexico. Stick exclusively to bottled or filtered water, even for brushing your teeth. Ice at restaurants and bars is generally safe as it is made in commercial facilities using purified water.

Street Food: Mexico boasts one of the greatest street food cultures on earth. To eat safely, follow the locals—eat at stands that have high turnover and a crowd of local residents. Avoid stands where food looks like it has been sitting under the sun for hours, and always wash your hands before eating!