You need:
Pressure washer with snow foam and attachement
2 Bucket system with grit guards
Microfibre mits (1 for paint and 1 for wheels)
Relevant chemicals - eg good wash chemical and a good no acidic wheel cleaner
Drying towels (to be dragged not rubbed) or if your flush a de-ionised water system so you can rinse the car dry (stops water spotting)
Also the less you touch the car the better so best regime is a pressure washer with a snow foam 1st, then a rinse with the pressure washer then a regular wash with mits, 2 buckets and grit guards after the snow foam and rinse have removed most of the grit, then a dry by microfibre deep pile towelling using the drag method or if you have the funds rinse with de-ionised water system then leave to air dry (best method as its no contact)
Best rule to follow is the less contact you make, the less scratches/ swirls you will acquire.