If you're reading this you probably know what "roleplaying" is as a concept, and have maybe done some of it - if not, have a look at our FAQ. In particular, LARP roleplaying is a little like freeform acting, it's improvisational, and there's a lot more to it than just the mechanics of the game. While they play a part in what you are allowed to do, they're not really where the roleplay comes from. Roleplaying is about making sure you act in character (IC) - i.e. you do what the character you're playing would do, not necessarily what you would do in real life. It's also about not spoiling the mood, acting in an out of character (OOC) manner can break the immersion other players have at that moment. In some ways this is a co-operative thing, in order to keep the mood, you need to work with the other players. This guide contains a few pointers to help you out.
Your character doesn't need to (and in fact shouldn't) know everything about the setting. There is a huge amount of information on the website, but your character is unlikely to have extensive knowledge of aspects of the world and society that do not directly concern them. Unless you have a reason in your backstory why you should know about a specific thing, it's safe to assume ignorance. This both keeps things balanced for new players and makes the world more interesting. You can model information (and disinformation) flow if your knowledge about the world comes mostly from what others have told you IC.
The nature of the game (not everything is defined, you are expected to ad-lib) means occasionally people have different views of how things work, and sometimes you'll come up against someone saying something about the world that doesn't tally with what you believe about it. Whatever happens, don't panic, drop out of character and have a big argument about what's on the website!
Firstly, not everyone is playing from the same page, other characters may be trying to spread disinformation. They may have been told something incorrectly IC. 'I've never heard of that - it's not that way where I come from. Are you sure?' is fine - generally if it's an OOC misunderstanding everyone looks slightly embarrassed, changes the subject and goes to thrash out what's actually going on with the refs OOC after the interactive.
The flip side of this coin is if you aren't sure and it isn't covered in the wiki, make statements that you can back up with your background rather than statements about the world as a whole. If it isn't covered in the website brief, it probably isn't something the refs think is important enough to need to be defined, but be aware other people may have defined it differently to you. Framing a statement as your character's personal belief makes it easier to argue your point in character if people disagree.
There are two levels to this - the first, most important is to have as part of your mindset that what happens in the game stays in the game - if someone's character kills yours it is not an attack on you personally. The same if their character disagrees with yours. (In general an assassination attempt is a compliment - your character is having enough of an impact on the game for someone to feel they have to take such a risky action). If you are having problems with this, talk to the refs. If you really can't get around this, this may not be the game for you. Conflict is a part of our setting, and we expect characters to antagonise each other and have fights.
On a more mechanical level, your character only knows things they have found out IC. You, the player, may know that those wiggly blue things you monstered on the linear last week are about to shoot magic out their nostrils and are only defeatable by MAGIC damage, your character doesn't unless they were there, or have been told about it IC.
In general, if you have something you don't want people to know IC, don't tell people about it OOC. Things slip into IC knowledge easily, unintentionally - would you have made that deduction if you didn't know XYZ OOC? At what point would you started to have suspect, IC, if you didn't already know the answer OOC? Even if you are happy letting people know your secrets OOC, you may be inadvertently be messing up someone else's roleplay.
Hit points, system calls and RESISTs (and hence '2 hit healing potions' etc) are all OOC concepts, really try not to use them IC. You should be able to convey any concept without resorting to describing the system OOC, if you can't explain them IC ('I have three hits left') it's probable you don't actually understand them in that level of detail IC. Although things have a definite system effect they aren't necessarily more certain IC than they would be in real life, it's acceptable to be slightly vague.
On the most straightforward level, don't start discussing what you saw at the cinema on the weekend - if you're tired of roleplaying and want to catch up with someone, leave to the out of character area. Don't make OOC remarks when you're IC.
Yes, we've all noticed that there's a Tesco bag floating in the Pool of Wisdom, or that the person playing the evil witch is the same person who played the dying maiden 5 minutes ago; but if you remark on it, you might completely spoil the feel of an encounter for someone else, and probably for yourself. Just because your hand's in the air doesn't mean that it doesn't distract other players just as much as if you'd made the remark in-character. Try to build up atmosphere, not destroy it. Try to always act as in-character as you can, and communicate things in-character. Don't say, "I think I know what happened here (OOC, I'm using Knowledge 3)"; or "the mage is the one at the back (*hand in the air* the one played by Bryony)". If you can't get something across in-character, then your character probably can't either, so don't say it. If you need to talk to a ref, do it in the least distracting way possible.
You've been hit with a sword three or four times. Yes, your character sheet may tell you that you still have at least one point, but you're hardly going to feel it top physical condition. When you are hit with a weapon, it slices into your skin, or crushes your flesh. You're not going to be thinking about your next hit for a moment - you're going to be thinking "OW that hurts". Roleplay your injuries, perhaps be a bit less effective when you're back in the fight; because, however many points you may have left, you're hurt. You might be angry about this, you might be upset, scared, or gritting your teeth; but you're going to have noticed. ... your character will develop personality in the way that they react to things like injury, rather than just going "5 hits... 2 hits... 1 hit... dying".
Turns out the game world isn't real. Yes, there are holes in the system. Yes, a real character living in the setting might start to notice that it was slightly strange the way nothing much happened in the world over the holidays. You are in charge of your character, and peculiarities of the game mechanics and the way we play just do not occur to them. In the game world someone really can take a sharp axe and whang you over the head four times without knocking you out. This won't be surprising, because in the game that's the way the metaphysics works.
Large portions of this guide were borrowed from Durham's Guide. If you have any questions or want advice, just sit down with another player and talk about it. Most of our members are quite happy to argue about the philosophy of roleplaying and discuss it at length, and will only be too happy to help. Likewise, if you feel uncomfortable about something or are unsure if you're doing it right, just ask for some constructive criticism from your fellow players when you're not in character. Larp in general is a very different experience to most things, and we all learn new things every time we play.