You'll need to disassemble some of your bike's parts and place it in a box with protective packaging ready for transportation.
Specifically, remove the saddle and seat post, handlebars, front wheel, and pedals. All parts must be individually wrapped for protection and placed inside a large box to accommodate them. In line with our general packaging guidelines, which also apply for packing bikes, padding should be packed into the box to ensure no parts of the bike moves inside the box during transportation.
Our friends at Stallion Cycles have provided a comprehensive step-by-step guide with images.