For probably the past 10 or more years (out of 25 continuous years of RV'ing), I store my slinky sewer hose right in a telescopic section of pvc gutter, and keep both ends of the hose capped while in transit.
When I go to connect to sewer, simply take the gutter out, telescope it to the reqired length to reach the connections, and either put a few block under the gutter, or I do carry one of those accordian tressle supports, which I'll put under the gutter. Takes literally on a minute or 2, and it's straight, properly sloped, and off the ground.
Works for me.
USAF 1965-1971; USCG Master
2002 Horizon 36LD - 2000 GMC Sierra 1500 4x4
Indian River, De