Back when I got my RV Dicor had not yet come out with their brand of roof cleaner.. What they told us then was, slightly translated. Think Kitchen Floor.
Mop (I use a long handled "Van wash" brush, a window washer's brush woudl work too)
Spic & Span
Back when I was a child and due to little sister's allergeries we mopped the floor EVERY day you first swept up loose stuff (Sweep it off the roof) then mopped with Spic & Span and water, Mixed as per package instructions, then mopped again with clear water (Rinse)
The differences in the kitchen floor and the roof
I use the brush, which slops a lot of water onto the roof
I do not mop up the mop water,, I just hose it off with the hose.
And I rinse with the hose (See last line)
OF course.. Make sure your shoes are good on a wet surface (GOOD Deck shoes) avoid the edges with your body,, The all won't hurt at all, but that sudden stop at the bottom is a serious problem.
(As are any interruptions on the way down).
Have only broken 2 necks so far (Thankfully they were on hose cut off valves, NOT on ME) "Falling" off the roof (Tossed the hose when done).
Home is where I park it!