1. Open the game in Topeka world and enter your own game world.

2. Select "Building" in the toolbar on the left side of the game screen, find the "Two-Bedroom Apartment" option, and click it.

3. Choose a suitable location on the game map, drag the mouse on the screen to determine the size and location of the building, and finally click the "Build" button.

4. After the construction is completed, click the "+"sign on the double-decker apartment to upgrade and speed up the operation. In order to realize the triple speed function, you need to buy corresponding acceleration props or discount packages.