Rinse your sewer hoses when leaving full hookup site?

I use a 2nd hose which has backflow preventers on it DO NOT insert small (Supply) hose into sewer hose, hold it at lesst 4 times it's diamater above the sewer hose when rinsing.

I will make sure there is a "hump" at the outlet end, then fill the sewer hose with fresh water and lift the Inlet end, thus "Flushing" the entire hose.