I just need to post that information for someone around!
The original post is from Grit Magazine.
Trailer backing can be one of the more vexing of human activities: More so if someone is watching you and especially so if someone is fussing at you about how to back up a trailer while you try to learn.
Although proficient trailer backing is no mystery, it takes practice: Much of the trailer-towing public would simply rather not run their rigs in reverse. Check the number of pull-through sites at the local RV campground for proof. But into each life, some backing up must come, so it’s important that you master this skill if you’re going to haul a trailer.
Moving in reverse requires only low speed, a cool head, vigilance with your mirrors, and knowledge that the trailer will move in the opposite direction that you steer the tow vehicle. A handy trick for getting used to this sometimes confusing characteristic is to place your hand on the bottom of the steering wheel and remember that if you push your hand to the left (turning the wheel clockwise), the trailer will tend to veer to the left and visa versa.
This advice probably isn’t going to make sense conceptually. You’re going to need to get out in the rig and try it out. For many, learning to back is easier without an audience or a guide, and the first backing exercise can be accomplished on your farm’s lane — simply pull ahead, put the truck in reverse, and back up as slowly as you can while watching the side view mirrors. If the trailer veers to one side, move the bottom of the steering wheel in the opposite direction to correct.
When you can keep your outfit headed straight in reverse, experiment with backing around a corner. This maneuver is not only handy, but it might be the only way to get your trailer into the shed, or up to a loading dock.
Once you find a good location for this exercise (best to avoid tree-lined lanes), pull your trailer past the corner and back up slowly. Watching the mirror on the same side as the turn, push the bottom of the steering wheel toward the curve — the trailer will begin to veer in that direction. When the trailer begins arcing through the curve nicely, gradually push the bottom of the steering wheel away from the turn to straighten the truck and trailer. Watch the front of the truck so that you don’t inadvertently hit a fence post as it swings around.
Beginners can seldom back through a sharp curve without pulling ahead at least once and there is no pride lost in that. However, with enough practice, you will be able to place your trailer wherever it needs to be and neatly extract yourself from situations that you accidentally pulled straight into. Better yet, you can take advantage of all the parking spots and dock bays left unoccupied by those who prefer to pull through.