I finally built a projection screen for my video projector. The aspect ratio of the screen is 16:9 and the size is 85" diagonal (188 cm wide and 106 cm high).
The frame is made of 21mm*21mm wood which was then covered with black fabric. Then I stretched a white cloth to the frame and a black cloth on top of that so light doesn't get through. All the fabric pieces were attached with staples and I think I used over 300 of them.
I might do the screen of a piece of MDF painted with the suitable color later, but this is better than nothing for now.