Move your camper into position so your sewer hose can reach the campground's sewer connection. In some places it may be necessary to connect two sewer hoses together in order to reach the campground's sewer.
Close both the gray water and the black water valve on your camper. The gray water valve will be relatively small and the black water valve will be larger. The black water valve should always be closed, but occasionally the gray water valve will be open---make certain it is closed.
Unscrew your RV's sewer cap. You should be able to do this by hand. The sewer cap is generally labeled. It is on the outside of your RV, on the same side of your RV as your kitchen sink. There is a door cover on some campers, but often the cap is left exposed, though recessed.
Push the end of your sewer hose into the sewer connection and turn it half a turn clockwise. You should hear (and feel) a "click" and the hose should be firmly attached.
Carry the hose (do not drag it) until you can connect the other end of the hose to the campground's sewer connection. This should connect in a similar fashion to the way the hose connected to your camper's drain, but sometimes a special coupling is needed. If you do not have the right coupling, ask at the campground if you can borrow one.
Open the black water valve on your camper. It will be the larger of the two valves. Allow the black water tank to drain completely. If the hose sags before it reaches the campground's sewer connection you may have to lift the hose so gravity can help the contents along.
Open the gray water valve and allow the gray water tank to empty. Again, you may have to lift the hose after the tank is empty to allow gravity to finish draining all contents out of the hose.
Close both valves and then fill the tanks half full of water. Run the sink or shower to fill the gray water tank and flush the toilet five or six times to put water into the black water tank.
Open the black water valve and allow the tank to empty again. Once it is empty, open the gray water valve and allow the gray water tank to empty again. Lift your hose to allow gravity to drain all of the water into the campground's sewer system.
Close both valves on your camper and then uncouple your hose from the campground's sewer system and then uncouple the hose from your camper. Put the cap back on the sewer connection on your camper. Hang the hoses up to dry with the ends hanging down so they will drain.
Flush your toilet four times and then add holding tank cleaner to your toilet and flush once more. Use holding tank cleaner that is biological and contains the proper bacteria for cleaning tanks. Do the same for your gray water tank, flushing the proper amount of tank cleaner (as per the manufacturer's directions) down your kitchen sink.
