If there are items on the floor in front of the wall, move them out of the way so you can easily access it.
Make sure the bucket is clean so you don’t add more dirt to the wall. Use warm water so the mixture combines better. Go with a mild dish soap so there’s no chance of you damaging the paint on the wall.
Soak the sponge in the water whenever you need more soap, but be sure to wring it out well each time so you don’t oversaturate the wall.
Wait until the wall is completely dry before you try to hang posters from it. Touch the surface with your finger to test it and be sure.
You can also apply the sticky tack to just the top 2 corners if you prefer. You can find sticky tack at department stores and online. Popular brands include Blu-Tack and Sticky Tack.
The hot glue can be easily washed from the painted concrete wall when you want to take down the poster. Use a laminated poster so it won’t tear whenever you take it off of the wall.
Use at least 2 clips for each of the top corners of the poster so it can be supported on the wall.
You can find velcro adhesive strips at department stores and online.
