User blog comment:Timmaster12d4/Tim's Tutorials: Things not to do/@comment-27357780-20170528013540

Well one way to get out is mine a stair-case to get out.

If you want to dig down, make sure to build a staircase and keep it lit with torches. If you don't, mobs will spawn. (Including bats which are harmless)

Be careful of lava. If you find lava but you need a ore that is across it, save some cobblestone and build a bridge. Make sure it 4 blocks tall in case of Skelabones. (My worst emeny of mining in caves)