For information on overland travel from Europe,
follow the link which gives full details of how to get there, documents,
equipment and GPS waypoints.
If you want the easy way, try Air France for
flights to Mali (Bamako), then contact one of the recommended guides who
can arrange everything once you get there. This option is almost
certainly considerably cheaper than driving all the way, but has a
significantly bigger environmental impact, contributes less to the local
economies and, most importantly, is not half as much fun!