The installation method is as follows:

1. Preparation: Confirm the installation location and ensure that the ground is flat and solid. Prepare the required materials and tools according to the size and design requirements of the octagonal pavilion.

2. Installation foundation: The foundation of the octagonal pavilion needs to be built. Use an excavator or hand to dig a foundation pit of corresponding size and depth, lay sand and gravel at the bottom of the foundation pit and compact it, and pour a concrete foundation in the foundation pit to ensure that the foundation is strong and stable.

3. Build the substructure: Assemble and install the pre-made cement octagonal pavilion substructure (including columns, beams, supports, etc.) in accordance with the requirements of the design drawings, using appropriate connectors and bolts, etc. Fix structural members to ensure the stability of the underlying structure.

4. Install the superstructure: After the substructure is completed, assemble and install the prefabricated cement octagonal pavilion superstructure. The upper structure includes an octagonal roof, railings, etc. Ensure that the connection between the upper structure and the lower structure is tight and reliable.

5. Waterproofing: If necessary, waterproof the ceiling and walls of the octagonal pavilion to enhance its moisture-proof and durable properties.

6. Subsequent decoration: After completing the installation of the main structure, decorate the octagonal pavilion as needed. You can choose to add awnings, lamps, flower beds and other decorative elements to make the octagonal pavilion more beautiful and practical.