The short answer is that I don't know.
The slightly longer answer is that just because a route is signed doesn't mean that it's the best route! Sometimes the interesting places are off the route.
However, a quick look shows options that are usually close to the river so it shouldn't be that hard to navigate those. Other options, away from the river, may be more difficult.
Normally on these routes there are information boards with maps. Take a photo and you have a map for the next section.
And remember that sometimes signposts get twisted so it's always a good idea to either have a way of checking your route or embrace the mystery!

If in doubt, find the river, look what way it's flowing and go that way
River, canal and sea routes were always my favourite type of route because I could just relax and not be lost. At least not for too long.

If one of your guidebooks is a Bikeline one you won't go too far wrong.