Three days is enough to get a real feel for Dakar without exhausting yourself. Here's the itinerary I give friends.
Day 1: Île de Gorée and Plateau
Take the morning ferry to Île de Gorée (20 min from the port). Visit the Maison des Esclaves, walk the colourful streets, lunch at one of the small beach restaurants, then ferry back mid-afternoon.
In the late afternoon, walk Plateau: Place de l'Indépendance, the Presidential Palace exterior, and the Cathédrale du Souvenir Africain.
Day 2: Markets, Museums, Mbalax
Morning at Marché Sandaga — Dakar's biggest market, chaotic and overwhelming. Lunch at Chez Loutcha for thieboudienne. Afternoon at the IFAN Museum for the best ethnographic collection in West Africa.
Evening: live mbalax at Just 4 U or, if you can get a table, Thiossane.
Day 3: Beaches and the Renaissance Monument
Drive west to Ouakam to see the African Renaissance Monument (the 49m bronze statue) and the surfing beaches at the foot of the cliffs. Lunch at La Calebasse in Almadies. Afternoon at Plage de Yoff.