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- Take a paint tray, put a generous amount of (dark but not anywhere near black) gray paint
- Add a pretty nice glob of white paint in the middle of the tray. Less is more!
- Take a rough roller (one that's been nicely loved), roll it in the tray so that the outside of the roller is soaked in gray and middle in white
- Paint your walls
- While still wet, go over the walls with a roller and minimal gray (like dry brushing but with rollers, fuzes the white together while keeping the rough concrete texture)
- Stand 20 ft away and see if the white is random enough. If not, the wiki recommends you take more grey to certain areas and not others.
Rough Concrete Walls from Hamlet, 2017 (set design by Jakob Weisblat and Maya Levy)
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There comes a time in a scenic painter's life where they have to actually use some semblence of artistic talent, maybe in this case to paint an actual realistic portrait/intricate landscape. Because you are likly an MIT student who probably does not have enough time for any of that, the wiki recommends printing a picture of the painting (if portrait of actor, use publicity photos + coordinate with costume persons) with the large printer in the ensemble office, use white masking tape or white gauff on the back sides to reinforce corners, and painting over the portrait. If faces are too hard, the wiki recommends painting everything but the face. No one will be able to tell from 20 feet away except the wrinkling on the paper and slight glaze will make it look slightly like a painting.