If there is a bottom board, it is usually tightened from the four sides with ropes. Ordinary small billboards do not have a middle In this case, it is best to use special glue for inkjet printing commonly used on the market to glue it on. If you want to achieve the best state with high viscosity, you must meet the following conditions: First, the billboard should not be too far away from the wall. The conventional distance is within Within 1 meter, secondly, when gluing, wrap it with spray-painted cloth strips around the billboard, and both sides must be fully glued. I have been advertising for 8 years, and I have never used this method. A piece of fabric peeled off the brand, I hope it can help you.