Minecraft wiki entry for Combat, associated text: Step One: Attempt to hook your opponent with the Fishing Rod. It is recommended to wield the Fishing Rod in your Offhand.
Step Two: Get into a Water Source to use your Riptide Trident, then use Riptide to go all the way up
Step Three: Before you reach as high as you can go, release the Fishing Rod to bring the Player or Mob up with you.
Step Four: Shoot them with your Bow in mid-air. They will take Fall Damage along with the Bow Damage.