How to throw a killer halloween party for teenagers ?

How to throw a killer halloween party for teenagers ?

so yes i am throwing a semi-huge halloween party with about 15 teens and some family but i want to know how can i make it a night to remember ? I need to know everything ! Can anyone help ? some details you might need to know:
Its being hosted outside,
I have a swimming pool
I have speakers outside
nice spacious backyard
large back deck with stairs
Its a costume party
I have bought spiderweb, skeletons, fairy lights, spiders, gravestones, pumpkin lanters.. pretty much everything.

please help !! every answer will help

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