Remove the headrests from the front seats.
Move the front seat all the way forward. Now fold the seat backs back until they are horizontal.
Fold the rear seat backs back.
To return the seats to their original position, repeat all these operations in reverse order.
Folding the rear seat backs
Remove the head restraints from the rear seats. Then fold the rear seatbacks forward.
Remove the headrests from the front seats
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Fold the front seatbacks back until they are horizontal. Then slide the front seats back until their folded cushions rest flush against the folded rear seats.
To return the seats to their original position, repeat all these operations in reverse order.