From Marrakech airport, taxis will take you to Marrakech for 100 dirhams (the equivalent of around 10 euros) during the day, and for 150 dirhams at night / early morning (around 15 euros). During the day and until midnight, you can also take the bus for 30 dirhams.
To then reach Essaouira (180 km), Agadir, Taroudant, Agdz and M’Hamid (Sahara), you can take a taxi / minibus or rent a car (PW / 4 × 4). Bus lines are also available (information at the train station, from the company Supratours or CTM).