You can reach the town where the wedding takes place, Schriesheim, via the tram line No. 5. Note:
If you are coming from Heidelberg, make sure to take the tram which heads towards Weinheim.
The stop is Schriesheim Bahnhof.
From the stop, it is another 1.5 km by foot. See the walking map. Alternatively you can catch a cab using the companies listed under Schriesheim Taxis above.