Has this event occurred previously?
In some cases, the special event may have occurred previously. If this is the case, you can start to collect evidence before the next special licence application. You can create an incident log for this, listing different types of amenity and good order effects that have arisen from the event.
This list may help you consider amenity and good order effects, but you could think of other examples.
It is useful if you always document any alcohol-related incidents in your community. You can use this incident log to help you.