This step is not optional :-). Locate the seatbelt sensor under the driver's seat and disconnect it. Then locate and unfasten the 2 front bolts holding the seat. Fold and roll the seat forward and unscrew the rear bolts as well. Lift the seat brackets up and remove the seat from the car. Place the seat in the same position as in the car on a level surface, to prevent damage to the brackets.

Repeat for the passenger side.

Screw the bolts back to make it easier to identify them when cutting corresponding holes in the new carpet. Screw them in completely to avoid stepping on them and damaging them.