Before you start cleaning the driveway, use a broom to sweep away any leaves and debris. This will stop patches forming where the cleaner wasn't sprayed on the driveway.
Before you start spraying the chemical cleaner, carefully read the instructions on the package. Put on your safety glasses and protective gloves. Starting at the bottom of the driveway, begin spraying the chemical cleaner onto it. Work your way to the top of the driveway spraying all over it with the cleaner.
Change the nozzle on the high-pressure water cleaner to the patio cleaning nozzle. Connect the high-pressure cleaner to the garden hose. Start at the top of the driveway and slowly sweep your way across and down the entire driveway with the high-pressure cleaner. Depending on the size of the driveway, this might take some time but it's a job that shouldn't be rushed.