Use the command //schem load followed by //paste in-game. :
Use the Litematica mod to view the holographic blueprint in-game. Optimization Tips HyCraft Lobby.rar
Move it to your Minecraft saves folder (typically located at %appdata%\.minecraft\saves ). Use the command //schem load followed by //paste in-game
If you are running a heavy lobby map like those from HyCraft, you may need to boost your game performance: HyCraft Lobby.rar