A new games store opened in my area and I said I would run some pathfinder games for them. I thought I would run some one shot adventures and then see how many regulars there are and start an adventure path, probably the new mummy's mask one.
What should I know about the rules that people find tricky and ones that come up a lot?
I have the core rule book, advanced players guide, advanced race guide, ultimate magic and combat, and bestiary 1, what other books should I pick up?
And any advice in general or things to watch out for?
I've just started running games as well. Read your scenarios and do your prep. Understand mechanics of combat contained in scenario. Go over combat section and conditions in core book. I find the condition cards and buff deck work well at low level scenarios with new players.
If you can, have players sign up before hand and then review their class skills. Knowledge will accumulate as you go. Don't be afraid to say you don't know something and look it up in game. Have fun and grow in knowledge and experience as your players advance as well.
Having a good grasp on the Grappling rules before it happens speeds things considerably. As for other books I'd say Bestiary 2 maybe.
I'm guessing that you will invite random people to play?
General Tip: Make sure everyone, who joins in, understands that it's a game for everyone at the table and that it's not about "You who are that awesome guy".
I find it that some people thinks that having a character with "important" back-story somehow makes their character more valuable to the adventure and the NPCs. Or that hogging all the attention will impress the rest.
The best player to play with and DM for is the one who picks a supporting positioned role and goes all in. The worst one stops the adventure by saying "MY character wants to do THIS instead!" and breaks away from the party.
Bottom line, tell them that they should be playing as a team, always more fun that way.Come with pre-writen character sheets, some people may choose to not play because they don't want to spend hours of reading rules for a game they might not enjoy. Also, make a very basic personality to the characters (players can then easly develope on that and you won't get crazy characters that you're not prepared for) and a connection between them all, giving them the reason to be a team. All just to ease the start-up.
You may be getting some new players and some more experienced, think about giving them appropriate roles. Give the guy who's been playing for a while (if there is one) the caster role.
THIS right here. If nothing else, THIS.
I was recently a new GM for PFS. (Actually, it was worse; I had only played a handful of games before that, I'm relatively new to RPGs, all the regular GMs weren't able to arrive because of Superbowl celebrations. We were able to scrounge together an extra table.)
I wasn't great the first time. I learned a few lessons. This is okay.
Prep is very important by the way. PFS scenarios will omit statblocks so be sure to have them collected in one place. You may have to apply modifiers to them and that's really hard to do on the spot especially if you haven't GM'd before. I learnt most of the combat rules but not all of them. Luckily I had people who helped, and that helps a lot. Don't be afraid to rely on other GMs (if you're GMing in PFS, most likely you'll not be the only GM at the venue).
PFS also helps because your fellow GMs can provide you with materials/maps until you start amassing a collection - as far as I know they're always looking for new GMs and can give you a lot of advice.
If you're GMing a home game though that's a bit different. Your most helpful people would be the players - after all, if you want to maximize fun for everyone, communication is important.
I was thinking of PFS but not sure how it works and how much you have too put into it?
Well, PFS assumes people will come in and out. Home games (even if you're running at a store) assume that the party is fairly stable.
As a new GM, I would have been overwhelmed if I tried to run a custom campaign. Even if you're doing a home game I would recommend you pick up an AP and run it by the book mostly so that you get familiarized with the system.
If you want to run PFS at a new place, I'd recommend you talk to a Venture Officer in your area or close to your area. They're very good resources to tap especially if you don't know much.
You can run an AP in PFS, but it still pretty much assumes a fairly regular party, you'll have problems if people come in and out. It requires more planning than a regular PFS session.
Do you know in advance there's going to be a group coming in or not? Has there been interest at the store? If there are people who want to play but you're maxed out at 7, would you be able to find other GMs to help you run?
Do you have another store that runs PFS in your area that you can visit and figure out some things?
You'll need to register yourself at PFS and be prepared to register others. You need a copy of the core rulebook and some dice. Maps and minis will also be required.
PFS is a nice way to get started. If you find you do have a very stable group (same 5 guys show up every Thursday night), then you can consider an AP.
PFS is broken into short 'chunks' or scenarios that are expected to be completed in 1 gaming session. Then if you have a different group of folks for the next 'chunk' it is no big deal. It is a separate task to be completed.
If you were running an AP and different people showed up you could get things like "I don't care what the barbarian did last week. He isn't here and my bard would not have cheesed off the baron that way."
They also tend to spell things out more completely for the GM. That is a real bonus when you are new to the role. AP's tend to have a lot that is open to GM interpretation. They might give hints like "If the party decides to chase down this clue, you might have them encounter a cave complex full of orc bandits." Then you have to make-up a cave complex full of orc bandits.
PFS comes with some pregen characters that people can start with. They aren't great but they are good enough to play and learn the rules.
The PFS scenarios are relatively cheap (some are even free).
If you want some advice on where to start with PFS, post a question on how to get started in the PFS forum. Several people will be happy to walk you through the process.
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If you decide not to go PFS, I would recommend you start with the Core Rule Book only. There is plenty lot to learn in just that book. Once you know you and your players have that down pretty well, then you can start introducing other books.