What you will need
-Nether Portal
-Pickaxe
Suggested: Iron, Diamond
-Flint and Steel or Fire Charge
Step 1:
First build a Nether Portal, If you have a Nether Portal skip this step, using Obsidian 5 blocks high and 4 blocks width but do not build in the centre, leave the centre 3x2 blocks of air and light up your flint and steel or fire charge. Then enter the portal to the Nether.
Step 2:
When you are at the Nether go to any part of an area of Netherracks and mine them with your pickaxe. Remember, do not go far from your portal as you may be lost in the Nether.
Step 3:
After you have mined your Netherracks with your pickaxe return to your World by going to your Portal, place a block or more of your mined Netherrack(s) and light them by using your Fire Charge or Flint and Steel and there you have it, you have a everlasting fire! Never place Netherrack near flammable items such as TNT, Wood, Wooden Planks, Leaves, Wool and Wooden Stairs.
Netherrack is very powerful with Fire that even in Rain or Snow, it cannot burn out, however it does have a weak blast resistance.