World Edit

[MinecraftLife634]

How do you select a region selection?

 

[HKMrox]

To use world edit, you first have to do //wand. You should then get a wooden axe. It won't work if you just get a wooden axe out of your inventory though. Once you do //wand, you left click on one block, and then right click on another. Then use //set [Block/Block ID] to change all the blocks within your region selection to that block. Say, if you left click one corner of the floor in a room, and you right click the other corner, and do //set Wood, it'll change the whole floor to wood.
I'm not entirely sure any ranks are able to use World Edit though, but I hoped this helped.

 

[JollyJon]

Or, if you want to create four walls, you can select a square or rectangle (one block on the floor, one in the air) and do //walls <block/ID>.

Here's a reference on each command. http://wiki.sk89q.com/wiki/WorldEdit/Reference