If you are done with the Basic, Intermediate, and Expert Commands, you are ready to program your very own command block! Command blocks were added in the 1.4s to give the player an opportunity to make their commands come to life. You can get a command block by typing in: /give @p command_block
So, first, click the command block. Put in ANY command you have learned here. Then, exit the command block (Don't use ESC), and either put a pressure plate or press shift and put a button. Then, activate the command block!