The best time to sort out your data is before you fly. Buy the eSIM while you still have wifi at home, install it, and you land in Mali already connected. No airport queues, no hunting for a kiosk.
Our Mali eSIM runs on Orange, the main network in the country. Two plans are on sale. The 1 GB plan lasts 7 days and costs $6.02. The 3 GB plan lasts 15 days and costs $16.06. The cheapest way in is the $6.02 plan, which is plenty for a short visit.
One thing to check first. Your phone must support eSIM and must be carrier unlocked. Most recent iPhones, Samsung Galaxy, and Google Pixel phones are fine. If you are not sure, look in your phone settings for an option to add an eSIM or a second data plan.