Before you pull out the vacuum and cleaning supplies, clear out all the obvious rubbish. Check everywhere thoroughly. There will likely be rubbish on the floor, under the seats and in the seat cracks. Toss out any wrappers, bottles, toys and other objects that your vacuum can’t handle.
Tackle floor mats
Pull the floor mats out of the vehicle and shake them out as much as possible. This will make vacuuming easier. Scrub them with soap and hot water or a foaming carpet cleaner and allow them to air dry completely before reinstalling them.
Vacuum, vacuum, vacuum
Vacuum both front and back seats, the floor and, if necessary, the boot. Vacuum every area of the vehicle where you can get the nozzle, including under the pedals and along the side door panels.