I'm putting on a big event in January 2019 (in California, if that matters) where just about all the revenue (something like $40K) will come in late 2018 and nearly all the money will go out in early 2019. The event might roughly break even, so how in general would I arrange to pay taxes on just the net, if any, once all the dust has settled?

Would I set up some entity to take the revenue and pay expenses in the meantime, then just withdraw the net as taxable income after the event? Or can I somehow just not treat that advance registration revenue as 2018 income?