Wednesday is Halloween, the one day each year when it’s good to be bad — or at least grotesque and frightening.

That doesn’t mean goblins and tramps should leave their manners behind. Etiquette experts and Halloween lovers say there are rules to follow, even on the scariest day of the year, for kids and adults alike.

RULES FOR KIDS

Teenagers should leave the trick-or-treating to younger children. By the time they’re 13, many teens would rather spend Halloween at a party with their friends than go door-to-door, anyway.

There are exceptions: Teens trick-or-treating with young siblings are all right, as long as they are meticulously courteous and wear a costume.

And it should be a real costume, said Todd Wolfe, who used to operate the Scream If You Can Haunted House in Clovis, Calif.

"I don’t like it when people come to my front door and have a T-shirt that says, "I’m a Bum,"’ he said. But he gladly forks over candy to trick-or-treaters of any age if they’re making an effort to dress up.

At the other end of the spectrum, Fresno, Calif., image consultant Cheri Bertelsen said, anyone who can’t chew candy shouldn’t knock on doors.

"I’ve had people come where they’re carrying a 6-month-old," she said. "That’s a little much, too. If you don’t have teeth, you probably shouldn’t be trick-or-treating."

Yes, under certain conditions. Traveling to a distant tract in hopes of upgrading your stash is not one of them.

Leah Ingram, the Pennsylvania author of "The Everything Etiquette Book" and a mother of two, said: "If you’re neighborhood-jumping because you’re greedy and you want to get as much candy as possible, that’s not cool."

But if children live in an unsafe or impractical neighborhood (such as a rural area where homes are far apart), it’s acceptable to visit friends or relatives and go trick-or-treat with them in their neighborhood.

RULES FOR HOMEOWNERS

No. Lisa Kothari, Seattle author of the children’s party guide "Dear Peppers and Pollywogs ...," said it would be cruel to punish a child whose parents have shipped them off to your neighborhood, even though they may have broken the previous rule.

"Too many hurt feelings there," she said. "Stay in the spirit of the holiday; get an extra bag of candy and give it out."

If you want to give something extra to a few of your favorite neighbors, Bertelsen said, that’s a great solution.

"When those kids show up, they get a little more than the average person coming to the door to make it a little bit different for them," she said.

Turn out the lights when the party’s over. Ingram said other than that, there isn’t much you can do.

"That’s sort of a rule that parents should teach their kids: Lights are out, then nobody’s home. You don’t ring the doorbell."

Just to be clear: This isn’t high-grade vandalism we’re talking about. Most carved pumpkins are going to be thrown in the trash within a day or two anyway.

But it would be unfortunate to let a child get away with no repercussions, said Cynthia Merrill, who has taught children etiquette for years in Fresno. She takes a gentle but firm approach to any misbehavior and suggests a quiet line of questioning that will get kids to think about what they’ve done.

"Go out, say, "I’m sorry, but what is it here you’re doing?" she said. ""Don’t you understand I had a lot of joy making that? Now you’re destroying it? Do you think you should be doing that?"’

Wolfe, who said he has dealt with a lot of property damage over the years, doesn’t hesitate to call police: "If they’re going to smash my pumpkin, they’re going to smash someone else’s pumpkins around the corner."

RULES FOR PARTIES

Everyone’s laughing, talking, having a great time, and you think you’ve figured out who you’re with, so you just reach over and give a gentle yank to see if you’re right.

Resist the temptation to do this.

"You never want to get into anybody’s personal space," Merrill said.

Ingram agrees: "What if it’s somebody you don’t know well? Or, God forbid, you’re at a party with people you work with, and it’s the company president. You’ve just pulled the rubber band on the mask, and it has slapped back on her face. You could put an eye out. That’s not good."

Instead, have fun with secret identities. Make a guessing game out of it. But keep your hands to yourself.

"Don’t look at it," Wolfe said.

Merrill agrees: "We live in a community of free speech and ideas and attitudes. It’s not your place to criticize someone’s costume."

Kothari said the only exception might be if you’re the host. Even then, it’s tricky.

"Take the person aside and have a quiet word about it," she said. "Perhaps they could make it less risque or simply change. One thing not to do is call public attention to the person and make it a big public scene."

Bertelsen said if you’re truly offended, leaving is always an option. Making an issue of the costume is not.

"Pointing out someone else’s error is not good manners," she said. "That would be rude itself."