Usually getting in Warnemuende is by cruise ship. So, my tip for those, that arrive by ship and stay here for 10-12 hours. Cruise ship shore excursions are expensive Alternatively, you may spend all your time in Rostock and Warnemunde, or exploring nearby surrounding by local train - the train station is 100 m near the peer. Another option is to rent a car and go with friends far away, e.g. to Potsdam to nice Sanssouci palace. The trip by car is 2.5 h in one direction, but visit worth your time.
Unfortunately, there is no rent-a-car agency in the Warnemunde port. The nearest one is in Rostock-lutten kleine (7 km) - Sixt, you may use a taxi (12 Euro) to get here.
Am Strom is the street along the old harbour. This is your starting point. You can go to the lighthouse, the beach or into the village.
While walking along the Am Strom waterfront you will be not alone; it's the favorite pastime of both visitors and locals.