To destroy the other teams base by breaking their obsidian and climbing the tower to the Ender Egg and clicking the Ender Egg. Capture Points are spread though out the map, hold one for a minute to gain gold to trade with villagers for upgrades.
I recommend at least 3 people a side, but for maximum fun, 6 a side would be better.
Play with mobs and animals off
Do not break blocks - expect for obsidian
Do not place any blocks
Wear your own teams armour
Play in survival mode - do not use any game changing mods