We've all seen the absolutely amazing tifo that AO Seattle constructed for Tuesday's United States World Cup qualifier. Now, you can see some of what went into making it. You'll notice that it's not necessarily glamorous work, sewing, painting, that kind of thing, but it does make displays like this possible.
It's also not necessarily cheap, as the AO Seattle twitter account pointed out. If you'd like to support this kind of work, consider purchasing something from their store.