You can read all the books you like on fencing (my own preference is one), but at some point (as with all things) you've just got go to up there and do it.
Which is why I spent several hours yesterday, after my now-habitual tractor yoga, up a stepladder, carefully heaving a four-kilo sledgehammer onto the ends of several two-and-a-half-metre fence posts the previous owner had stuck in a Most Inexplicable Place.
The orchard/chicken is being enclosed.
Today, my formerly soft office-worker's hands are feeling slightly crampy as a result and the rest of my body is feeling just a tiny bit stronger. Good thing too, as I also have a large veggie plot to enclose with even more serious fencing, before installing a couple of rotivating pigs in January.