Difficulty: Moderately Easy
Step1
Avoid the American chain restaurants at all costs. Enough said.
Step2
Avoid most American-looking storefronts. Many restaurants, not just in Mexico but around the world, cater to Americans, who spend more time and more money traveling than any other nationality. Americans also, by most estimations, are fools and prefer blander, watered-down versions of true ethnic food. If the place looks like a place you've seen in your local shopping mall, move on.
Step3
Find small shops. Taquerias are all over in Mexico. Of course, there is no exact rule here. Feel it out. Follow your gut—both stomach and instinct. Chances are, the tortillas are fresh, the salsas are flavorful and the beans and meat are hot and plentiful, not to mention cheap.
Step4
Try the roadside stands. From tamales to stuffed peppers to tacos, these stands are very cheap and usually delicious. Ignore the lack of American-standard sanitation and relish the home-cooked flavors.
http://www.steveklotz.com/blog/wp-content/uploads/2007/10/mexican_food_neon.jpg