Typically there are three cars, or other forms of transport, for the wedding party:
CAR 1 - takes the bride and her father to the ceremony. After the ceremony, this car takes the bride and groom to the reception.
CAR 2 - takes the bridesmaids and the mother of the bride to the ceremony. After the ceremony, this car takes the Best Man and all of the bridesmaids to the reception.
CAR 3 - takes the groom's parents to the ceremony. After the ceremony, this car takes both sets of parents to the reception.
Guests
You may want to consider providing transport for your guests. For example:
Central meeting points, take your guest to and from the ceremony, reception and home; or
Central meeting points, take your guests to reception and home; or
Central meeting points, take your guests to reception only; or
Central meeting points, take your guests home only.