3 Wither Skeleton skulls - Kill Wither Skeletons, which are black skeletons found in Nether fortresses (in the console edition, they spawn elsewhere in the Nether as well). Wither Skeletons have a 2. 5 percent chance to drop a skull. 4 blocks of soul sand - Soul sand is dark sand found throughout the Nether.
It is highly recommended that you have a Diamond Sword with Smite V, Diamond Armor with Protection IV, as well as a Bow enchanted with Power IV or V. It is also recommended to fight the wither in the Nether, but in a smaller area. That way, the Wither will not destroy anything of value.
If you’ve beaten the Ender Dragon in The End, this may be a good place to summon the Wither. The Wither will focus its attention on the Endermen. You can either let the Wither kill the Endermen indefinitely for a good supply of Ender Pearls, or get the Wither to half health so that it can’t fly anymore, allowing the Endermen to finish it off.
It’s important to create the frame before adding the skulls, since the last block you place must be a skull in order for the Wither to spawn.
Avoiding the Wither’s attacks while hitting it as much as possible is the only way to proceed from this point until the Wither dies. The Wither regenerates health, so your attacks have to be consistent.