We rented quads. It's the perfect activity for the adventurous. We later discovered that it was quite the work out because we woke up with incredibly sore muscles.
It's great fun to speed over the dunes. It can be a family event too and we saw children as young as seven on quads designed specially for their smaller size.
Any questions we had regarding the quads were answered during our inital orientation. Then they let us loose. It was one of the highlights of our trip. There are several companies that rent quads and you can find them on the internet.