From the airport
Train: You can take different trains e.g. the ICE 515, from the airport Frankfurt (they depart every 15 minutes) for the central station "Mannheim Hauptbahnhof". From there take the S5 to get to the station "Stahlbad". The hotel can be reached in a walking distance from less than 5 minutes. it's a 98 minutes trip. You can choose between a single ticket (2,10€), a day ticket ( 6,50€) or a ticket for three days (15,80€). Within the ticket price you can take the train, as well as the bus in Weinheim.
Taxi: The trip takes 40 minutes and costs around 120€ - 130€.