Disconnect the Frigidaire washer power cord.
Slide the washer away from the wall so the back of the machine can be serviced.
Remove the screws around the edges of the rear access panel. Lift the panel off of the Frigidaire washer cabinet.
Rotate the tub drive pulley by hand. Roll the belt off the pulley as it rotates. Slip the other end of the belt off the motor shaft.
Rotate the pulley. Roll the new belt onto the drive pulley. Loop the other end around the motor shaft.
Replace the rear access panel. Install the screws that hold the panel in place.