If trekking, you should be in good physical shape and carry and drink lots of water to prevent dehydration. Head covering is also recommended as the midday sun is exceedingly strong and can even catch a well-hydrated traveler offguard. Good, sturdy shoes, whether general running/walking type or hiking boots are recommended for the treks as the terrain can be difficult to traverse on some of them.
Many people find walking poles to be helping for the flatter parts of the trip, but in general, they are a hindrance, especially when navigating steep areas. Use your own judgment when carrying them, but be advised that they will be dead and awkward weight if you find you don't need them.
Lastly, be careful of snakes in brush although most are nocturnal.
talk
The local Dogon language is spoken by everyone, but due to its popularity with tourists French remains the lingua franca. English is spoken by only a handful of tour guides in the entire region and practically no one outside the handful of cosmopolitan relatively speaking base camps/towns. A working knowledge of French is essential unless travelling with one of the few guides who speak English.
respect
Dogons are very spiritual and visitors should be very keen to respect their beliefs. One should always ask if it is appropriate to photograph something. Altars may look like piles of dirt to the untrained eye and religious buildings may look like just a house, both of which along with people, unless you ask permission should not be photographed.
itineraries
People generally plan any number of approaches to Dogon Country. Most common is to spend about three days which allows one to visit several villages, stay in them amenities are generally rather comfortable all things considered and then get out. Day trips are also quite doable to a number of villages, such as Nombori. Villages like Songo can be visited in a morning.
There is also the opportunity to spend a week or more hiking the entire escarpment. This is recommended only for the truly adventurous who want to take the time to plan out the trip and be prepared to buy supplies en route.