1) Understand the basic White Wolf rules
I'm not sure how much she's actually looked at the rulebooks, so that would be my first recommendation. She probably doesn't need to read them cover to cover yet, but she should especially know the basic White Wolf "roll Attribute + Ability" mechanic and the common difficulties/number of sucesses need. It wouldn't hurt to know some of the common rolls as well, like Perception + Alertness and Strength + Melee
2) Understand 'fae seeming' and 'chimerical' objects.
One of the hardest things for me to understand about Changeling was the "fae seeming" and how chimerical objects interact (or fail to interact) with the real world. The best explanation that I ever read was comparing Changeling to Calvin & Hobbes. Hobbes is a chimera based around a specific real-world object. Normal people, like Calvin's parents, only see the physical object, the stuffed tiger. Calvin, however, sees the "real tiger" version of Hobbes and can talk to him, climb on his back, hug him, get pounced by him, etc.
3) Look at the Changeling: the Dreaming-specific rules and concepts
She should study the specific Kiths, as they are a pretty large part of the game. She would need to know how each one's powers and weaknesses work. The players are going to want to try out those powers right away,so it's important that she's ready to handle those. She should also understand Glamour and Banality, as those are very key game concepts. She should at least skim the section on Arts and Realms. Those may not come up in the first session, however.
4) Make her own character, but don't play it
I would recommend that she makes her own character to get a feel for the system and the various options that the players have. (She shouldn't actually run it in the game, though.) That will let her see how the various parts of the character interact. White Wolf usually has good step-by-step instructions for character creation and they always have an example of it, but having her make her own will give her a better grasp on that than just reading it.
5) The first session should be character creation....
For the first gaming session, I'd recommend having the players make their characters at the same time. That way, your daughter can answer any questions that they might have and cover any concepts/options that might not be clear, like Kiths.She can also encourage players create bonds between their characters, like being relatives, friends, etc.
It also lets the players see what the expectations are around the table. There are no character classes to choose from, but some players may want to choose a Kith that no one else has. The relative 'nobility' of each Kith can come into play as well, becausehving a party of a Redcap, a Pooka and an Eshu is going to play a lot different than a party of several Sidhe and a Troll.
By allowing the entire first session to be character creation if needed, you make sure that none of the players feel rushed.
6) ...And running through some basic scenarios.
Once the characters are made, it would be a good idea to run through some basic role-playing and rules scenarios, as there probably won't be enough time for a full session.
These would be things like:
- Trying to get information from another fae at a bar
- Chasing someone down the street
- Getting in a fist fight
- Trying to sneak your way into a secured building (or, for specific Changeling fun, out of a mental hospital)
The important thing here is to try different combinations of attributes and abilities and to give her a feel for narrating scenes. I would play these almost as video-game 'tutorials: the characters are in a certain place and then this happens.
What do they do?
7) General Storyteller tips
- She can always call for a short break from the game if she needs to think something through.
- If she gets stuck on a rule, make a quick, common-sense judgement and then move it. She can always look it up later.
- The players know that it's her first session, so she'll cut them some slack.
- Start out small and work your way up from there.
Changeling the Dreaming is one of my favorite games and I wish your daughter a lot of luck!