Separate the sandy desert from the sky with the help of the horizon line.
If you look at the desert from afar, you can see the dunes rising one after another. Draw them in the form of wavy lines. The hills in the second plan are smaller than in the foreground.
Finish drawing the sand using the wavy lines.
The cacti in deserts are big. Two or three sprouts go often from the base.
Draw some plants. Draw cacti of the smaller sizes which are at the distance.
There are facets on th plants, they have thorns. Mark them with the help of the curved lines.
Draw the thorns in the form of short strokes. Start drawing the sun.
The heavenly body in the desert is low. You can draw it using a compass or a round object of a suitable size.
You can draw the sun higher or lower, it depends on what time of day you are drawing.