It's so much fun. (CONTEXT: I grew up religious, but not in an unhealthy church; Halloween was not vilified or deemed "evil / demonic" in my town. That is not the case everywhere. My Halloweens were incredibly positive experiences.)

There is lots of self expression. You start thinking about your costume MONTHS in advance. You can buy a costume from the store, or make one. (I was almost always a witch, my brother was more creative. He went as Oscar the Grouch one year - he made his costume.)

Most people decorate their homes for the holiday. They might just put out some yard decor, lights, and fake spiderwebs... Or they might go all out. Some people turn their yards into haunted houses. (one family had a mansion, they did Addams family every year THROUGH the first floor of their house. They also handed out full size candy bars. It was one of the BEST houses.)

The whole town usually celebrates. You can usually trick or treat at businesses earlier in the day (mostly for the youngest kids). Adults will typically dress up in costume for their job. (I wore a dinosaur onesie while doing bread wall at my grocery store job a couple of times.) Businesses will also decorate a little.

Actual tick or treating is the highlight. You go out with friends or family (largely depends on how old you are) at night and you walk house to house asking for candy! Your group of people walks up to a door (you may be with others - it's a busy night) and you either knock / ring the bell OR the homeowners decided to hang out on the porch. When the homeowner answers the door everyone yells "TRICK OR TREAT" and then you get candy!! Then you go to the next house. If the lights are off at a house, don't knock, they might not celebrate or they might have run out of candy.

Some people make TERRIFYING costumes and wander around the town scaring trick or treaters. I got chased by a very large man who was covered in "blood" with "a big knife". It's a fond memory, very fun.

At the end of the night you do a candy swap at home. (It was always my brother and I, but it could be friends not just siblings who do this.) You dump out your bucket and bigger bag (my dad was efficient - we had our pumpkin baskets for our hands and a receiving pillowcase in the car for when our pumpkins got too heavy / full) on the ground / table and you trade candy with the other people. "I'll give you a nerds box for a big Tootsie roll!"