Tips to Defeat the Ender Dragon

Here are some tips/supplies you should bring. It is okay if you fail at first, killing the dragon may be more difficult for some people.

Materials:

Food: approximately 8-15 pork chops/beef. Optional: Some golden apples.
Weapons: Iron sword, preferably Diamond. Enchanted is even better. As many snowballs possible. A bow and about 3 stacks of arrows. Try to get Sharpness or Smite enchantments for the swords and Infinity or Power enchantments for the bow.
Armor: Iron armor is good, but the dragon cannot hurt you in diamond armor. Beware, it can still knock you down from high places.
Blocks/Items: An enchanted iron/diamond pick, again, preferably diamond. This will be used to mine endstone, as the dragon cannot destroy endstone. Optional: Some strength, speed, or instant health potions.

Tips: Shoot all the health regenerators possible from the ground. Some may be a little too high, so you will have to manually build a staircase up the obsidian tower. Remember, the 'regenerator' is explosive, so it is recommended that you shoot it from a distance rather than up close. (Photo of the regenerator crystals below.) Falling from a tall tower can result in death.
Once all of them have been destroyed, you can focus on killing the dragon. Try shooting it with your arrows, and when it gets slightly close use your snowballs. That is where the snowballs come in handy. When it decides to swoop down and attack, dodge it and smack it with your enchanted (hopefully) sword. Repeat this process, and if you want shelter use your pick to dig up a shelter in the endstone.