Guide for how to behave or what to expect at a Panto in England?

Question

I have been invited to a Panto in England.

Now have I been told quite a bit about it, but I think it is going to be quite a shock for people who have never been to such a theater performance.

Is there a guide for people who want to go and join in with the public at Panto's?

I have seen descriptions in books, like Mercedes Lackey's A Scandal in Battersea, but it is easier when the guide is 'free standing' and not part of a book.

Added 2022:
Since asking this question I have been to some Panto's and those had a good part of the public adults (coming without kids) and for them a lot of the fun is in subtle language jokes. As someone who learned English as a second language and does not live in the UK I missed quite a few of those jokes. It was still fun but not as much as it could have been.
From what my friends said, the quality of the panto is even more important for the adults than for the kids, so if your English is up to it and you want the full enjoyment, check out the reviews and/or join up with locals who have done the homework.

Answer 1

There are plenty of online resources, including:

• A stranger’s guide to Panto – or – How to get the most out of it!
• What is pantomime? A guide to this most British of festive institutions
• Wikipedia - Pantomime

Here is an extract from the first link:

Most Pantomimes are loosely based around a fairy story, nursery rhyme or children’s book. Some of the most popular include Cinderella, Sleeping Beauty, Snow White and Peter Pan. Common to all are certain characters and traditional audience responses that I’m going to give a short quick-start guide to here.

The Dame

This character is the most rude, silly and outrageous of them all – traditionally played by a man. There is never any doubt about this – Panto Dames are no drag queens! The will be larger than life, have a store of wise-cracks, double-entendre, huge dresses, wigs false eyelashes and more makeup than you seen in the whole of the cosmetics section of Superdrug in Southside! Despite all this, they’re goodies, and invite the audience to respond to catchphrases and jokes, and will keep on encouraging until they get the enthusiastic response they want. When the Dame enters, you cheer, whoop, clap, and make good noises!

The Baddie

The baddie can be male or female, depending on the story, and as you might guess, is the bad guy. When they enter (usually accompanied by ‘baddie’ music and one or two hopeless sidekicks) the audience need to shout “boo!” as loudly as they can.

The Heroine

Often the title role, this is played by a pretty young woman. Scripts vary, and sometimes she can be a bit wet, but is often portrayed as quite a clever, feisty, young thing, but always with a kind heart.

The Hero

Also played by a young woman, usually with a lot of leg on display! This encourages the practice of ‘thigh-slapping’, something that Panto is famous for. The hero is clever and brave, will fall in love with the heroine at some point, and together they’ll defeat the baddies and true love will prevail.

The Good Fairy

A fairy or spirit that observes the hero and heroine’s plight and helps them out. Usually a gentle and kind character, full of courage, but often with rather poor jokes!

Assorted other characters include the stupid goodie, the stupid baddie, a talking animal (cat, mouse, horse, cow), someone who’s hopelessly in love with the heroine, the hero’s friend and an older King/Queen/Parent.

Audience participation:

Other than cheering the Dame and booing the Baddie, there are plenty more opportunities to make a noise, For example:

Character calls “Oh yes it is!”

Audience respond “Oh no it isn’t!”

Repeated three times, no more, and can be adapted or reversed according to the situation.

If there’s some sort of activity going on behind a character that they stupidly can’t see or hear, then yell “it’s behind you!”

At some point, the goodies will often require the help of the audience, sometimes everyone doing some sort of ridiculous action, sometimes yelling or singing a magical spell. Whatever it happens to be, you must join in or everything will end up really, really badly. It’s all down to you.

Sometimes, one or two very special audience members are called upon to go on stage and help out the goodies. This is a very important role and if called on you have to do what is asked so that the audience can cheer a really cute child, or have lots of fun at the expense of a hapless adult. Either way, it’s a great honour to be picked.

Source A stranger’s guide to Panto – or – How to get the most out of it!

Answer 2

It's not that hard.

The audience at pantomimes is mostly children (and their grandparents) many of whom will be going to the theatre for the first time, so the performers keep it simple. The heroes are good and the baddies are obviously bad. The "fourth wall" is not just broken, but largely ignored, and the performers address the audience directly to tell them when to boo and when to cheer, and when to shout "He's behind you!" or "Oh no he isn't".

It is really pretty obvious, as it has to be to cater for the young and inexperienced audience. Just go with the flow!