This is a long, broad inter-dune valley running roughly north–south; it's thought to be the bed of a fossil river. During and after good rains this is carpeted in luscious green grass that attracts dense concentrations of game. It's the park's most famous location, and where Mark and Delia Owens lived. If you are visiting the northern section of the park for five to six days, then my advice is for you to save this as a highlight for your last couple of days.
Because it is the park's most famous area, and relatively close (35km) to the Matswere Scout Post entrance, this is the place where you're most likely to see other visitors. It's also the area with the most campsites.
Towards the northern end of Deception Valley, on the west side, a track splits off to pass beside the four Kori campsites (codes CKK1 to CKK4), which are about 500m apart. The most southerly one is located at GPS:CKK1 and the most northerly at GPS:CKK4. They're in fairly sparse bush on the edge of the main pan, and very generally close to any animal action there – though bushes obstruct their views.
Deception Valley's other six campsites are all set north of the pan, higher up in fairly thick woodlands. There are six of these (codes CKD1 to CKD6); the first three on the south side of the cut-line road, and then three on the north side. (The middle one of these is found at GPS:CKD4. It consists of a roughly circular area that has been cleared of trees and bushes. Each is separated from its neighbours by a few hundred metres, making them very secluded and private.
If you're heading out of the park then, to find your way out, simply drive towards the north of Deception Valley. There you'll find several small junctions with signposts, as the tracks along the valley are intersected by the straight cut-line road. Head east to GPS:JUNCT1, and continue on to sign out at the Matswere Scout Post at GPS:MATSWE.