The most significant rule in desert photography is: deserts need to be photographed in the early morning or late afternoon light. This because much of their detail and texture is subtle and can be lost if you take pictures when the sun is higher in the sky and consequently light is much stronger. The gentle light at sunrise and sunset may cause the desert to glow beautifully orange or red, and the low angle means that even a ripple in the sand will cast a small shadow, giving contrast and definition to your picture.
If you don’t have other choice than taking pictures in the heat of the day, then consider to shoot with the longest lens you have and try to photograph something a long way off that is distorted by heat haze. You may be able to photograph a shimmering mirage, where the heat haze resembles water. A powerful telephoto lens will exaggerate and magnify both of these phenomena.