(You can easily skip this if you already have some RP experiences since this guide is directed towards complete newbies and people that never had anything to do with RPing.)
So, you want to get into RPing or are mildly interested, at least? Despite what you might believe, RPing is not just awkward fetish outlets on Skype/Discord/mobile or people running around half-naked doing ERP in MMOs. I'd even dare to say that these aren't really what I would consider "real" roleplaying at all.
The shortest explanation for roleplaying would be collaborative writing although there are also RPs that use mechanics similar to Pen and Paper/Dungeons and Dragons. Anyway, the roleplaying we are doing here is also called play-by-post roleplaying in some circles. This basically means that you and your play partner/s take turns in writing in-character postings. In-character means that you write from the POV of your character - which you have to create first, of course. Let's start with the needed steps to get started in the first place.
1.1. Learn about the setting/world you want to RP in. In our case, this would be Horhsal. You don't have to learn absolutely everything and could also start with something simpler like Earth (although you won't be able to RP with us in that case since Earth doesn't exist in our RP universe). If you want to go with a pre-defined fictional world, learn about the most important stuff and what makes the world different from others first. This doesn't have to be super extensive and others will help to ease you in step for step. Think of it like getting into a new game.
1.2. Choose a setting/RP story to join. This is only possible if an RP site has multiple stories to offer. A lot of other RPs don't but we have RP hubs that feature different places and features. It's best to start with something simple or ask others what a good place for beginners would be. If an RP site is only about one story/setting, you don't have to worry about this kinda stuff.
2. Create a character. This might be difficult for you at first since you have never done it before. You should know that creating an RP character is somewhat different from creating a character in a video game with character creation. You usually have to define their strengths, weaknesses, and abilities yourself which can be a bit overwhelming. Plus, you should watch out to not create a Mary Sue - a character that can do everything, is liked by everyone and basically super boring. RP characters should be balanced and have both pros and cons to them.
If you don't know if you can handle this yet, create someone simple, like a regular person that doesn't fight. You could also create a character that doesn't know much about the world because they lived in a backwater town which is a great way to learn more about it because it requires less prior knowledge.
Don't forget to choose a look for your character. How this is done usually depends on the site and you should read the rules to know which images are accepted. We, for example, do not allow real people/photos and only use drawn images (both self-made art and animanga). The character should also make sense within the world, meaning that you shouldn't use a race that doesn't exist and isn't allowed. Speaking about looks for a character. Do not forget that the character images you choose for your character are not the same as the character you are creating. We only allow original characters. So if you want to, for example, use Ran Yakumo's looks for your character you could do that but you would need to give that character a new name and personality because Ran Yakumo doesn't exist in our world. Never forget that "character you are using for images" =/= "your character".
3.1. Plan your first RP scene with other players. You can't just RP by yourself. Well, you probably could but that wouldn't be much fun. RPing means that you use your character to interact with the characters of other players. Even the most experienced player was once a newbie so they should be able to help you get started. Don't be afraid to ask for help.
3.2. There might still be a question in-between - how can a character even join a scene? This is something that is tough to answer and one of the reasons why mutual planning with others is a good idea. Don't use something like "They bump into each other". I mean, you could use that but it would be a bit cheap after a while.
How characters join a scene is highly dependent on the situation, you could also think about establishing relations between characters before the RP starts which is a pretty normal thing to do. The plotter is a good forum area to do that. If you, however, do not want that - which is fine, really, your character could be a traveller that doesn't know anyone in the area - then you should try to set up a starting situation with other players or ask the staff to summon a random event/situation if that is more your thing.
You could also have your character just meddle with other peoples' business if that is part of their personality (but ask the other players first).
4. Once you have something planned it is time to start your first RP session. Here are a few pointers for that:
Don't just decide what the characters of other players are doing - you can only control your own character. Trying to control the actions of other characters is considered powerplaying and frowned upon.
Don't confuse player knowledge with character knowledge - your character won't know everything that you know. Doing things that your character can't know because only you as the player know it is called meta-gaming.
Don't confuse character and player. Even if another character hates yours that doesn't mean that the player hates you or your character - they are just playing out their character's personality. You aren't the character and vice versa. Roleplaying means that you try to get into someone else's shoes - your character's.
Give other players something they can reply to. Just holding monologues with your character and ending postings in a way that make it difficult to reply to isn't a good way to RP with others. You could, for example, say something that someone else will need to reply to or do an action that requires the action of another player.
And, the most important tip, just try to have fun and learn things step by step. You won't be a master RPer in a few days. Heck, I consider myself just average even though I have years of experience. It's all about how well you can work with others to create good stories.
5. You are probably still waiting for me to explain how to even write postings, right? Don't worry, I got you covered there.
The best way to start is to have the other player/s with more experience do the first one, so you can see an RP post in action. You will probably notice a few things, such as that the other player describes things in a narrator style while the character talks in first-person. This can differ from RP to RP, though. The usual procedure, however, is third-person narrator (past-tense) and first-person dialogue (present since it's the characters actually talking). Dialogue is indicated by using "...." while actions are done in normal sentences like in a novel. For example:
The general knew that this next meeting was important for the country's future. The invasion had to be stopped, otherwise, their future would look dire. He arrived just in time, took a seat, and started speaking:
"The army's morale is low and we lost too many men and women in the last battle. I am not sure if we can even survive the next wave of attacks."
The general looked concerned and it was clear that he was close to giving up hope.
And so on and so forth. In this example, another player - maybe another general (you have to consider that only high-ranking people have access to this meeting) - could answer him. What they could say depends on their personality and their player. They could agree that things look hopeless, ridicule the other general and call him a coward or give him a speech filled with hope. If there are more than these two players a third one could do something as well. If there are just these two - or another player decides to do nothing (this is also possible but should be telegraphed since going on and on without giving the third player a chance to do anything would be unfair) - the first player has the chance to react to what the second player did. If the second player decided to try to give the general hope the first player could then decide if his general lightens up and regains some hope or shakes his head and says it's pointless. Only you can decide your characters actions, don't forget that.
When it comes to the length of posts, it highly depends on the players and your own style. Some players like to write short and efficient posts while others prefer longer, more detailed ones. Both are fine. You don't need to describe everything happening in exact detail while it is also a good idea to describe things that might be important. If you think that the looks of a room or something are important, don't forget to include them in your post (but don't repeat something all the time. Explaining it once is enough).
I hope this guide was enough to get you interested in roleplaying or at least satisfy your curiosity. If you want to know more, don't shy away from asking us. You can also use the RP testing grounds if you want to try it out without needing to create a character or learn about the setting since anything goes in there and the scenes in that forum are non-canon.