To start off, you will need to do the command '//wand'. This will give you a wooden axe.

To select your 1st position, left-click
To select your 2nd position, right-click

The most basic command is the set command; select your positions, then do '//set <block>'. In the <block> you can type (for stone) stone, minecraft:stone or 1.

The next command is '//replace'. What you need to do is '//replace <the block you want to replace> <the block you want to be there>'

The next command is '//walls'. What you need to do is '//walls <block you want walls with>'

To copy your selection, type //copy. Wherever you stand is where you have copied it from.
To paste your selection, type //paste. This will paste it where you stand.
To copy, then get rid of your build, do //cut. This has the same properties as //copy.
If you want to rotate your clipboard. copy it then do //rotate <90|180|270> WARNING: Don't do any numbers other than 90, 180, 270 and 360
If you want to flip your clipboard, do //flip. If you face up or down when you flip it, it will be upside-down. If you look forward, if will flip it around.

To undo a change, type //undo
To redo a change, type //redo

To stack your selection, do //stack <number> <north|east|south|west>
To move your selection, do //move <number of blocks> <north|east|south|west>

<MORE TO BE ADDED LATER ON>