It is important that one way street are mapped correctly, routing won't work correctly if you don't. Roads are two-way by default (unset) just set them to the correct one way if needed, just check the arrows point the right way. Turn restrictions, for example "no right turn", also need care to get right as they apply to a pair of roads at the junction, and they can be a little more difficult to get correct. You can check them, after a while, with OSRM to see if the work in the way you expected. see
https://help.openstreetmap.org/questions/32420/turn-restrictions-and-routing-engines