[Tut] How to make a room black. (Pictures included)

I know some people don't know about this and it's actually really simple.
Click Spoiler to see the images

I've provided screenshots so you know what I'm talking about.

1. Select any room!
   
   
2. Go into the catalog and select "Spaces". Find the following wallpaper/flooring.
   The wallpaper is the 19th to the left. The flooring is the 5th to the left.
   Make sure they are RED
   

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3. Buy the wallpaper/flooring and use it as your rooms.
   

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4. If you don't have one already, go buy a moodlight, any moodlight will work.
   Once you have a moodlight put it in your room and set the settings to this:
   

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   Dark blue, background only and drag the bar all the way to the left.
   
   
5. You have just made a black room.
   Feel free to decorate your project if you haven't already!
   

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