Things You'll Need
Instructions
Open the "Inventory" menu and select the bucket. Find a lava source and fill the bucket.
Find a pool or waterfall and pour the lava from your bucket into the water. This creates obsidian blocks. Use a diamond pick axe to mine the blocks and store them in your inventory.
Open the "Inventory" menu and select the obsidian block.
Use the left trigger button to construct a frame that measures five blocks tall and four blocks wide.
Open the "Inventory" menu again and select a fire charge or the flint and steel. Use the left trigger button to ignite the obsidian blocks. Six nether portal blocks will appear in the frame.