Use a Halter
Never lead your horse by the reins; the bridle’s headstall is designed to put pressure on his mouth or poll to leverage and steer from his back. This same setup is unwieldy for leading from the ground. A headstall can also come off or shift as you lead your horse through a challenging part of the trail.
Instead, use a trail halter. A lightweight rope halter with a long, thin lead rope is easy to pack in your saddlebag, even if you’re only on a day trip and have minimal gear. A trail halter correctly places pressure to cue your horse to lead and is familiar to him.