https://dev.bukkit.org/projects/worldeditMake sure to download the correct version that will work with the version of MC your currently running.
- Download world edit zip
- Add the world edit zip into your plugins folder
- Add your favoured schematic into the Schematics folder
Plugins>Worldedit>Schematics
(The schem folder will be created once you use a command in game where it is required or you can make one in that directory before hand)
- In game do //schem load mcedit <schem name>
- Text will appear in pink if it has loaded properly for you
- To paste your project best to use //paste -a
(It may take a few tries until you get it in the correct position you desire as sometimes users will copy their project from odd positions)
-use //undo to try again.
Have a practice with some small builds of your own first. WE can be overwhelming sometimes for first timers. Read and view some tutorials and be patient. If you need any more assistance feel free to ask. Hope this helps a tad.