For one thing, if you use a service such as a taxi, have your shoes shined, etc., make sure to ask in advance what the price will be--otherwise, they can charge whatever they want. You might also carry your valuables in a "Mexican wallet" which can be strapped on your upper arm or leg or hung around your neck under your clothing.
I found the Metro (subway) to be useful and the downtown areas to be safe (remember, this was the 1970's-80's), in particular in the areas where the streets are named after rivers and foreign cities. However, certain tourist areas such as Plaza Garibaldi were full of hucksters seeking to separate tourists from their money.
When I was there, I dressed like a Mexican, in button-down shirts and slacks--no short pants, which would identify you as a tourist, and definitely no blue jeans with a white T shirt. This was effective in one instance when a Mexican family stopped their car and asked me directions, but still, many recognized me as a Norteamericano.
At the time, I found a guidebook entitled The People's Guide to Mexico (Santa Fe, NM: Muir, 1972) to be very useful. The book has been periodically updated, the latest edition having been published in 2012. The supplemental website offers tips on traveling to Mexico including how to cope with red tape, what sort of weather to expect, upcoming events, etc. It also includes a blog.
Hope this is of some help. And to your daughter, buen viaje!
Thank you!! Some great ideas :)
I have no plans on vising Mexico but that website is very informative.
Glad I took a peek.
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