If you want to create a lobby with barriers, start with a barrier with a color that you think looks good as a background and terrain for walls. Then, create sections for instructions and detail with item images and text. Lastly, add padding and margin to add negative space and furnish the lobby up.
Optional: Add a section for players to preview areas of your map.
Make sure that all the barriers are set to no collision.
. For future reference make it a little bit longer, like adding more steps, etc.