Here are some lessons that I've learned in learning and teaching to play collectible card games (CCGs) in no particular order.
There is a learning curve.
I have been playing CCGs for nineteen years now, and many other boardgames and card games before then. I like to think that I have a fairly good grasp on how these games work. However, there are things that I realized over time (it took me a good two years playing Magic: The Gathering before I got the grasp of deckbuidling for that game). Thus, it is important to start new players with the basic concepts of the game and her play with simple decks first, then getting to more complex ones.
Back when I was playing Doomtown actively, there was a player I knew from playing Legend of the Five Rings (L5R) who wanted to try out Doomtown. So he played with my playgroup. At the time my playgroup, who all started playing at the same time, had mastered deckbuidling for the game and we had refined the decks we played over months of play and with every expansion that had been released. Needless to say, he was overwhelmed and commented that we should use beginner decks with new players. I think my response was to blink at him. I have since learned that lesson.
Winning is important to most beginning players.
I still have a hard time wrapping my mind around this one. Growing up I played a lot of boardgames with my step-brother and other family members. They were all better players than me generally and I rarely won. In fact, I remember the single time I won a game of Stratego against my step-brother (it was while he was watching a hockey game). The point is, I never expected to win and if I did win, it was a huge achievement. I still had fun playing though, and I worked hard to master the games that I played.
Flash forward several years to when I started playing L5R. There was a very active play group in Saskatoon at the time, so I sat down with four or five other players to play with my Phoenix Kiho deck. I won. One of the players I was playing with was the one mentioned above who soon after tried out Doomtown. I realized that he was expecting an easier time, and that I was probably given an easier time that first game that I played. Which may have worked for others, but didn't work for me, because one of my motivations for playing is to get better.
The point here is that winning is important to a lot of people, and can be a good motivator for them to continue playing.
Winning is not everything, but it is important to focus on.
This is actually a lesson that I learned in Monopoly. When I was about eleven or twelve years old I was obsessed with Monopoly. I had a book about Monopoly (which was the first analysis I read of a boardgame) which pointed out that in the actual rules of Monopoly there was no money in the middle that you won by landing on Free Parking. In fact, this money in the middle house rule slowed down the game! Furthermore, a game of Monopoly should last no more than two hours! The reason that games of Monopoly sometimes took legendary amounts of time to complete (if they finished at all) were because the players had stopped focusing on the winning condition: to bankrupt your oppponents.
While I have learned since then that when teaching someone a new game, starting with, "The goal is to win," doesn't work quite as well as I once thought it might. While it is important to note what the win conditions are (and the end-of-game conditions), most people don't appreciate being told that their goal is to win.
In CCGs, this focus on winning is one of the most important things to keep in mind when deckbuilding. "How does this deck win?" is something that a deckbuilder must ask herself through the whole process. Once that element is built into the deck, then you can focus on how the deck can respond to the local metagame.
Factions help to draw new players in. Story too.
The first faction-based game that I played was L5R. Set in a fictional medieval-Asian themed world, L5R has a storyline based around a number of clans vying for control of the Emerald Empire. Each clan has a different theme -- dishonour (Scorpion), politics (Crane), magic (Phoenix), military (defensive -- Crab; offensive -- Lion; cavalary -- Unicorn) and the forces of evil (Shadowlands). When I entered the game I was facinated by the Phoenix and Crane clans. This not only focused my deck types, but also focused my collection of cards. Cards for other clans I could trade for more cards of my clans. In addition to this was a rich story, part of which was told in the rulebooks, part of which was told in the flavour text on the cards. Clan was set against Clan, so there was even a reason to battle with opponents in the game. (Over time these inter-Clan rivalries became like the relationships in Gossip Girl, taking on every permutation thinkable.) My love for playing and stories that go along with it date back to Transformers, but the story that was written for L5R, especially for its first story arc was truly epic and got me playing.
Another part of the story in L5R was that it was interactive in that players could determine the outcome of the story by how they played. In organized touraments, players would declare for a clan and if enough players won for a particular clan that clan would get a benefit in the story and sometimes would get a card representing that win. For the world championship that determined the resolution of the first storyline, multiple endings had been written for each clan respectively if they won. As clans were elminated leading up to the finals, those storylines were destroyed. In the end the final two players (representing Crane and Lion respectively) decided to share the win, causing the story guru to destroy the remaining endings and create a new one on the spot.
It's easy to understand why L5R players were passionate about their game.
Your playgroup is the game.
Especially with deckbuilding games, the people you play with make the game playable. Because the game is constantly evolving (if it is still being released), the decks you play with should be constantly changing. Part of the metagame (game within the game) aspect of these games is that there is a reactionary element to deckbuilding depending on what is currently dominant. Most games have answering strategies to strategies, and part of the fun is finding what those answers are. In the last few years my playgroup for the active games that I play has not been playing as much, so although I continue to follow the games, I have not been building decks as much as I had in the past. The nature of deckbuilding games requires a level of commitment by players that isn't required for boardgames, as so much of the game is focused on deckbuilding when not actually playing. Although the players can have differing levels of commitement, there has to be a base level of commitment for these games or else they don't really work.
The more cards you have access to, the richer the game experience.
When I started playing Magic, the card pool that my friends and I had access to was fairly small. We were in high school and didn't have a lot of money to spend on the game (even if we did, there wasn't a lot of it available until Fallen Empires was released). However, as the card pool expands, the more options open up. Learning which cards are more powerful than others is possible, as you don't have to play with all of the cards you have of given colour or faction.
New games often suffer from having a small pool of cards to build decks with. However, while the card pool is small, the learning curve is a little less steep (without added choices of more cards), and with additional cards deckbuilding becomes more diverse.
The real objective is fun.
I once saw a group of kids playing Magic. An older kid was instructing how to play and was not using the rules that I was familiar with. I was tempted to go over and give them a quick rules summary, then realized that as long as they were having fun, whether or not they were playing the Magic I knew and loved or another, it didn't really matter.
The wonderful thing about CCGs is that they are both fun at a social level, in playing with other people, and fun at an indivdual level, in deckbuilding. And because they are constantly changing, adapting to new cards and new decks makes these games continue to be fun for a long, long time.