I don’t know the full route out, but from memory, get as far as the dog & duck pub, by either going under the railway bridge to side of sherwood pines or down the road, then go straight on over the road at at dog & duck, via left under the railway bridge up to the old abbey (I think!) up to peafield lane, cross peafield lane and pick up the bridleways to Sherwood Forest, through Sherwood Forest on the bridleways out through dukeries training range. This brings you out at the Netherfield Lane / A616 roundabout, which isn’t far from where you need to be.
I can’t remember the rest of the route out, but it involved crossing the road into the woods opposite and through to clumber, maybe even picking up the national cycle route but its not difficult to piece together from there or ammend the route above with the map to pick up the cycle route sooner