If the balloon arch can't lean against the wall, consider supporting it with a bracket. Brackets can provide additional support to keep the arch stable. Use specially designed balloon arch, usually made of metal or plastic, with stable structure and high enough to support the whole arch. Put brackets on both sides of the arch and ensure that the brackets are firmly fixed on the ground to ensure the stability of the arch. If there is no special balloon arch bracket, we can consider using other materials to make our own brackets. For example, build a frame with metal pipes, wood or plastic pipes, and then put it on both sides of the arch to provide additional support. When setting brackets, ensure the connection between brackets and arch is firm and reliable, and make proper balance adjustment to ensure the arch is stable. Attention should also be paid to safety issues to ensure that the brackets and arches will not pose any danger to the people involved in the activities.