Open up all the screened windows you have on the RV. This will create a crosswind in the vehicle and can significantly help in cooling the temperature.
Hang a camping fan overhead. These are battery-powered fans that you can purchase at most any camping store. These fans can hook up onto the ceiling and give off a nice breeze. This can be especially nice when you are sleeping.
Use cotton sheets at night. Flannel or wool sheets will insulate the heat more. Cotton, on the other hand, is a more breathable fabric that will allow airflow.
Cook all your meals outside over the fire. Using the stove will generate excess heat that will stay in the RV and warm the inside.
Cover the windows during the daytime. This will block out the sun and prevent the direct sunlight from heating the interior of the vehicle.
