I've never had to teach mine to roost, but from reading on here, lots of folks do. They set them on the roost after dark each night -- I think usually about a week of this does it. What's natural for them, I believe, is to find the highest spot, so you will read on here to have the roost higher than the nest boxes, to prevent them from sleeping in the nests. I have a couple who kept sleeping in spots higher than the roost, and had to block one of them off to prevent injury. One hen still sleeps on a storage container which is higher than the roosts, but she is the loner of the flock anyway. The rest cuddle together on the roost.
There are a couple of considerations here. My roost is 3' high and I have large fowl. They fly about 6' horizontally to come down off the roost. Larger birds can injure hips, etc. jumping straight down, so people put in ladders or steps of some sort if there is not much horizontal space. Another is, they can manage on a round roost if it is wide enough, but for a large bird, something like a broomstick is probably not very comfortable for them because their feet don't wrap as much as some birds' do. Mine are the wide side of a 2x4 and they walk around on it as if it were solid ground.
If they're not sleeping in the nests, which in time will mean poopy eggs, I personally wouldn't worry about it.