I find it's best to avoid hot temperatures and direct sunlight as it dries the water too quickly and leaves evaporation marks and smears
I always wash and wax my car in the shade for this reason.
Start with the wheels, hose them down first then wash them with soapy water and sponge.
Rinse the body of the car, starting from the top and working down, make sure as much loose dirt and debris is removed as possible.
Using lukewarm water and plenty of shampoo wash the car using a lambswool mitt, again from the top down.
Rinse the soapy water off the vehicle, make sure it's all removed.
Dry the vehicle using a chamois or microfibre towel.