Clean the tires first. Doing this will halp you prevent any overspray of chemicals onto your paint. They will be washed off when you wash the car. Don't dress them until it's dry though.
Make sure you use two buckets when washing. Fill one with the soapy water and the other with just warm water. After washing a body panel, dip the mitt into the water bucket to try to get as much dirt off of it as possible. This will help prevent swirls and small scratches. You can also use a leaf blower to get as much water off as possible before using the drying towel. Using the blower only really works if your car still ahs a nice coat of wax on it and the water can bead off easily.