I tried two different providers in the 2 months I’ve been here, and they both sucked for different reasons. One had was so new and unpopular I could never get credit recharges from street vendors, and the other one was too expensive, so I ended up going with the same provider that everyone in my family uses. That way, we just buy recharges in bulk, place them in a big box and we can all use them.
So I went to the provider store, and they had two tents with three tables set up. You bring your own unlocked phone and choose a phone number among the ones lying around, looking for a “pretty” phone number if you can still find one, they take your name and address and you pay 300 CFA Francs (about 0.50 USD and about the same in Euros) and you have your number.