1.) Type a command into a book and quill.
2.) Left click a command block while holding the book.
The command will be inserted into the command block.
Place a command block:
Left click a quartz block while holding a book and quill. The quartz block will turn into a command block. The command in the book will also automatically be inserted.
Left click a cobblestone block while holding a book and quill and all the text in the book will be cleared.
acb.set - allows a player to use NoOpCommandBlocks
*Note: This effectively gives a player access to command blocks! You should ONLY give this permission to players whom you trust!
The book and quill in unmodded Minecraft does not allow you to move the cursor. This means if you make a mistake or would like to change something at the beginning of the text, you have to erase the entire command and rewrite it.
Instead, go ahead and right click into an existing command block and go ahead and write the command in the command block like normal. It's easier to edit a command in the command block than it is with the book. When you're finished, select the entire command (ctrl+a) and paste it into the book.
If you like my stuff or want to see some of my plugins in action, head over to playminecraft.net!