Congratulations!
You character Sheryl has been accepted. You are so excited to use her, so you immediately scour the forum for an open thread. You see one! And immediately begin.
Now, you have never roleplayed with the character, so you go and post, saying your character runs into this total stranger and has no connection to them whatsoever. Oh, and since you're a little nervous about this new character, you don't want to do anything out of character, so you play it safe. They don't even notice the other character. And, oh, since all you're really sure about is what you've written in your application, Sheryl will be thinking about her deepest darkest secret as she walk in.
This seems natural, right? You've just begun with this character - you're not comfortable with her/him yet, the other characters has never roleplayed with your new character, and you just wrote an application detailing important life events? We should stick to the safe stuff, what we're sure about, right?
However, these behaviors enforce an assumption that your character has no back history beyond what you wrote in your application and was just plopped into this setting. Though this is the first time you have begun to actively write your character's story, they have already existed, formed relationships, and experienced daily life without you writing every experience.
But this is difficult. We are not yet aware of our character fully and we don't want to make mistakes, right? So what can we do?
Here's some Tips!
First - don't be afraid to make mistakes: If you are writing and you suddenly realize the thread isn't working out, all it takes is a simple PM to the other Roleplayer. "Hey, I don't like where this thread is going, could we abandon it, maybe try again? Or could we move it to the Alternate Universe forum?" It may be disappointing, but if you really feel as though you completely messed your character up, most roleplayers would sympathize. BUT! Better than abandoning a thread, accept it! If it is something that still makes the characters interesting to you, keep it, even if it wasn't what you expected the character for. Most of your favorite roleplaying will come from the unexpected.
Takeaways : Mistakes do not have to be permanent - you can always try to arrange something with the other roleplayer. However, taking risk can lead to mistakes, though this can provide amazing new development. Don't play it safe!
Second - BE AWARE OF WHO YOU ARE INTERACTING WITH: This is a HUGE one, especially for a Hogwarts thread. You've just made a sixth year... That means s/he has had five years of interacting with pretty much the same group of kids. Unless s/he is a transfer student, s/he should probably know the names of most to everyone in her year (it appeared that Harry did), should recognize fellow Housemates, and should have some sort of relationship with housemates of the same year. It seems unrealistic that two Syltherin fourth years should have to introduce themselves if they have both been going to Hogwarts for their full four years, especially as they would be attending classes with these people.
This applies to grads, too even if it is a little harder to track. Remember, your grad probably went to Hogwarts, and most of the people they meet probably did. Though it is hard to track when each character graduated, a quick confirmation of age is enough to figure it out. If they are seven years apart, they probably would not recognize each other from school. If they are only off by a few years, they may vaguely recognize each other. If they are the same age, they should recognize each other, and may even be acquainted, depending on their House and personalities. Other grad circumstances to consider - would they know each other from their line of work, from their alliance, etc?
If you want, you can become more nitpicky. If your character is a troublemaker, perhaps they know past troublemakers because they have done their research. If your character follows Quidditch, perhaps they know the professional players. If your character wants to be a politician, perhaps they have looked in to current politicians and can recognize them.
Another point - most purebloods should know each other. They are usually all related in some way and with their pride about being who they are, they typically choose the same company - each other. Remember, Draco recognized Ronald as a Weasley on sight.
And with that, my last point. Your character's parents. If your character's mom is an Auror, and you meet a girl who is the daughter of an ex-con, you'll probably recognize the surname. Your characters are, in some ways, influenced by their parents. They probably recognize anyone their parents may know.
The important thing is - never assume these characters are strangers, simply because one is a stranger to you. It is more realistic (and more fun some times) for characters to have a nice web of existing relationships that you can play off of.
Takeaways : Be aware of who you are roleplaying with, and any connections there might be between theirs and yours. Take note of : age, house, interests, factions, blood status, careers, family ties, and more. Don't be afraid to use the past of your character that you haven't written.
Three - Daily dealings reveal a lot: So you have this new character, and you immediately want them pitted in the war between good and evil, want them to be involved in a a complicated love octagon, and would appreciate a near death experience.
As fun as these things may be to roleplay, until you know your character well, it will be hard to pull any of these off. Secondly, it will be hard to find anyone willing to start a plot like this cold turkey. So what threads are you left with? Boring ones? No.
A few open threads of your character sitting down for breakfast, using the restroom between classes, or relaxing in the common room may sound boring, but this is, realistically, the sort of thing that constitutes 85% of your character's day. So, if you are struggling to begin, this is where it may be good to start.
Now note : If you simply post "Sheryl sat down to eat" it isn't incredibly likely that you will have people fighting to post with you. Really explore what makes your character unique in these threads. Express to the people around your character, non-player-characters or not, what you can see about your character from a glance. If your character is clumsy, don't be afraid to have him trip and spill orange juice. If your character loves history of magic, perhaps she is doodling a picture of the 11th century goblin wars. Use mundane circumstances to highlight what is noticeable about your character.
Takeaways : If you are struggling to begin, start with the daily routine. Let the simple scene be a blank canvass that you can highlight your character's unique features against.
Four - Don't exclude your character from the plot: PA has a pretty rich history, and most characters above the age of thirteen cannot escape the fact that it somehow impacted them.
Events : Was your character there? What were they doing at the time? What were their family/friends doing?
People : Names such as Jess Potter, Ne'Os Emof, Keith Nicholas, Kingsley Shacklebolt, the Potters, etc should not be foreign to your characters.
History : PA's history and that of the Harry Potter world should be somewhat known to your character. There should be few excuses for your character not knowing Voldemort, Harry Potter, Grindelwald, Dumbledore, the Battle of Hogwarts, the wizarding wars, etc.
Takeaways : Figure out where your character was during key events. Be aware of those your character would have heard about. Don't let your character be ignorant to general history unless there is a reason.
This is still under construction!
Note: None of this is absolute. There may be circumstances that allow two sixth years to be strangers, not every pureblood knows every other pureblood, and just because you both worked for the Ministry doesn't mean you have to be know each other. In my opinion, it is a good rule of thumb though to relate before you push away. If you can't think of a reason WHY these people shouldn't know each other, then let them know each other. (And vice versa)
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