I have found it best to disconnect the towed vehicle, turn both around, and reconnect.
I tried backing my Jeep ONCE on the tow bar. It moved about 5 feet straight back, then the front wheels SLAMMED over against the stops in a full left turn! Luckily, that was just barely enough that I could get the truck by the cars that had me blocked.
Some will say they have done it, with no trouble. That's fine. I tried it, and failed. I will NOT try it again.
Disconnect, turn around, reconnect.
Better yet, pay attention and don't get into places where it becomes necessary. In all my years of towing a vehicle, it has only happened to me once, and that was due to other people parking in my way.
As for trying to hold the steering wheel, I have read of at least one incident where somebody tried that, and wound up with a broken wrist!