Minecraft wiki entry for Things_not_to_do, associated text: Mining in a staircase pattern
Finding an open-mouth cave on the surface
Mining In A Dripstone Cave (left) Strip Mine (right)
Placing ladders or scaffolding while digging
Digging a 2×1 hole while standing between both blocks or on the block opposite the one being mined
Strip mining (Digging down in a staircase pattern then changing to a horizontal 1x2 pattern)
Repeating the steps of digging down 3 blocks from the surface, placing a ladder on the bottom block, standing on that ladder, then mining the blocks below