Instructions
Prepare and assemble important mining tools and materials. Before venturing underground, you will need at least one mining pick, a sword and some torches. Craft mining picks and swords from sticks and stone, iron, gold or diamonds. Combine sticks and coal to create torches.
Locate an existing cavern or begin digging your own. Face a block you want to remove and hold down your left mouse button to dig until the block vanishes.
Descend slowly into the cavern. Use the scroll wheel on your mouse to equip your torches and right-click on a surface to place them. Light sources allow you to mark locations, illuminate areas deep underground and keep enemies at bay. Avoid dropping large distances, as this damages your health and may kill you. Left-click on a surface while having a block equipped to create ledges or staircases where there are large drops.
Defend yourself against enemies. Because "Minecraft" enemies tend to congregate in dark underground passages, you should have your sword equipped when you are not actively mining or placing torches. When you encounter an enemy mob, press and hold your left mouse button to swing your sword continuously until the enemy is dead.