First, map the gate and its patrols in detail. Then build a small diversion—maybe a timed explosion or a false signal—to draw the guards away. While they’re chasing the noise, set up a hidden tunnel or a concealed ladder that leads directly into the courtyard. Make sure the path is wide enough for the warrior but narrow enough that no one will see the footfall. Keep the route light‑faced; use damp cloths or mud to hide the tread marks. Finally, coordinate a signal—like a lantern or a shout—so the warrior knows when the guards will be at their lowest vigilance. When the diversion hits, slip in, and you’ll have the element of surprise, all without anyone noticing a single step.