Begin by giving your seats a quick vacuum, or carefully wipe with the dry cleaning brush to remove any bits and also give the fabric a bit quick refreshing.
Mix together the cleaning solution to use on your seats. Dish soap is so gentle, lifting grease stains while refreshing the fabric, and washing soda is also a cleaning booster that leaves your seats happy. And both are safe to use on fabrics. Add the hot water, and give it a quick whisk.
Carefully dip the cleaning brush in the mixture, and then work over car seats in a circular motion. You're not looking to soak the fabric - just slightly dampen it to lift any stains. This also helps to remove any pilling from the upholstery.
Wipe the car seat with a towel, and keep on working until all seats have been cleaned. Lower the windows, and let air dry.
Finish by giving your car another vacuuming using the hose attachment, and then spritz with linen spray. You'll love your wonderfully smelling vehicle!