When it comes to alternative modes of commuting in the city, Mexico's capital has very good infrastructure and very cheap public transport. The metro system is extensive, covering virtually the whole city with up to nine different routes. You can find a map of the routes and stations in every metro entrance and you can also buy your tickets there. Having entered the metro with your ticket you can change as many trains and routes as you like without using another ticket. The bus system is also very good, and then there are the "peseros" or midi-buses that are not quite as comfortable as the bus or the metro, but take you anywhere and everywhere. Public transport is generally quite safe, though you should be wary of traveling late at night. At rush hour public transport can be quite uncomfortable. For ladies traveling by metro, the first two cars of every train have been reserved for them and for young children so that they may travel more comfortably. All public transport is ridiculously cheap.
Another obvious mode of transport is the omnipresent green beetle taxi. These taxis are cheap and easy to find, but they can be dangerous so it isn't recommended to use them. You should pay a little extra and use your international cell phone rentals to call a sitio-radio cab. Always be wary of crime in Mexico City and make sure to lock your doors and keep your windows wound up, whether you're driving or taking a cab.