A Band is a magically-bonded group of people, formed to help them overcome adversity and take advantage of the magical items known as Standards.
To create a Band, you must obtain some form of Standard, and all prospective members of the Band must have the Binding Thread Of Fate spell cast upon them and the Standard. Once two or more people have been bound to the Standard, the Band is formed, and can formally be registered with Wheelhouse. If the Band wishes to transfer their bonds to a new Standard, only one casting of Binding Threads of Fate is necessary to do so, and you must register your Band’s new Standard with Wheelhouse.
Only members of the same nation can be bound to a Standard and join the same Band; the magic of the Standard depends upon national oaths and a level of common culture to function, and so multi-national Bands cannot occur without significant expense to expand the enchantments of the Standard, such as with the Song Of Many Tongues item.
Bands cannot contain more than 50 members; the magic of the Standards that bind them together simply cannot connect more people than that without failing in some critical way.