When you are riding a Mountable creature, and the creature obeys your commands, you are considered Mounted.

While Mounted, you use the mounted creature’s Movement instead of your own. Your own movement is still deducted at the same time, however, meaning you cannot move 60 feet on a horse, dismount and then move, as your Movement would have depleted.

While mounted, you share Initiative with the mounted creature. The mount cannot act independently under normal circumstances.

While mounted, you can spend your AP to have the mount perform its actions.

Mounting a creature takes 4 Action Points.

Dismounting a creature takes 2 Action Points.

Being forcefully dismounted makes you start your next turn with 3 less 3 Action Points, and knocks you prone.

While mounted, when you are affected by Forced Movement, instead of moving, you must succeed a Endurance check with a DC of 5 + [The Amount of Forced Movement in Feet] or be forcefully dismounted.

See: Barding