If there is a center aisle in the church, the parents of the bride sit in the first pew on the left and the parents of the groom sit in the first pew on the right as you face the alter.
If there is a center section of pews with two side aisles, the parents of the bride walk down the left aisle and sit in the first pew on their right and the parents of the groom walk down the right aisle and sit in the first pew on their left. Both parents will then be seated in the center section of the church with the bride’s parents on the left and the grooms parents on the right as you face the alter.