Park politely and use common sense, don’t take up more room than you need and don’t block someone else in.
Leave gates as you found them, open or closed unless posted otherwise.
You don’t just walk down trails without any regard for anyone else you might encounter, there is a very specific and well-defined etiquette and right of way to follow.
Horses and pack stock only yield to each other and everyone else must yield to them. If you have a dog, move off the trail to the lower ground if possible, try not to be higher than the horses, and make contact with the riders, they will tell you how their horses are with your particular encounter. If you approach from behind, calmly announce your presence and intentions. Horses and other pack stock can frighten easily, so avoid sudden movements or loud noises. Believe me, you do not want to be responsible for a thrown rider.
Hikers yield to horses, everything else yields to hikers. Hikers going downhill must yield to hikers going uphill (uphill hikers have the right of way)
Bikers yield to horses and hikers going uphill or downhill. Courteous hikers will often get off the trail for bikers to let them continue with their momentum, however, this is a courtesy and is not to be expected. Bikers going downhill must yield to bikers going uphill.
By always picking up at least one piece of trash that is not yours compensates for the litterbugs, and it also sends a message about environmental awareness and doing what is right.