You need to get all the information of your building: real dimensions, color, design, etc.

Convert the measurements using 5 feet = 1 cm.  Round your measurements to the nearest foot, ie. 34 feet 6 inches goes to 35 feet.

Break down your building into geometric figures and get needed materials to build it.

Build your building to scale.

Decorate with paint, paper, etc.

<-- Process <--