Enjoy Mate, heres a few practical tips
Make a check list before your event so you don't forget anything on the day, some ideas as follows
spare gloves & tops
tear offs or roll offs
bucket and brush to wash numbers if muddy day (not much chance lately)
spare levers and other spares you have (no good in the shed)
have you got all your club membership done, Ambulance subsciption joined, race licence or one day stuff sorted
bike preparation & checks (at least a week before so you have time to get that last minute stuff)
Bike stand
spare tubes if you get a flat, levers, mallet etc
get to track a bit early, suss it all out feel relaxed as you have plenty of time to get ready
chain lube
spare air filter for dusty days
tools you may need on the day
poweraid or lots of water to drink
food
chair
A warm coat for winter (ok i'm a Vicco)
A camera for the missus to take shots with
Esky with good Victorian beer, not that Barbed Wire shit you blokes drink
(get ice on the way so those beers are well chilled at days end)