For the imitation canvas on the railings, I use "torck paper" (used in the catering industry).
From which I cut strips
Which I treat with a mixture of Polyurethane varnish and paint as colouring agent
I hang these up and let them dry, so that I get straight strips of paper
If I want to cover railings, I cut strips in the appropriate width and length,
These I treat on both sides with a mixture of Polyurethane varnish and speaker glue
As soon as they start to dry a little and feel like sticky tape, I apply them and shape them into the right shape with a small brush and a hair dryer.
Hope this clarifies things a bit, for me it has been a process of trying many types of paper and techniques, but the above works very well for me, and in my opinion comes close to reality (because of the lighting used, the "canvas" shines through, but later under the right lighting it looks very realistic in my opinion.