I always start my OC's with the basic infomation.
Name:
Sex:
Age:
Race:
Weight:
Height:
Hometown:
Current location:
Sexual preference:
I will talk about every one in detail.
Name
Names are hard. Coming up with a good name is a very difficult task and I'm gonna be honest. Google translating a word to japans is not a good name. I know Ikiryō sounds cool but trust me,no one would call their child "wraith" and they just so happen to be a wraith. I always try to think of a common name for that Universe. It's easy with MLP because you just call them whatever they do. For example one of my pony OC's is called Artsy Cleff becuase he is a musical artist. My main Creepypasta OC's real name is Edward V. Panwell because he was born a regular person with a regular life. He then becomes "Dr. V" He was give this name by the police and media due to the way he received his victims. He was a therapist. The V is because he often carved a V into his victims body or leaves a V written in blood at a crime scene. So it all depends on the universe they live in. The best way to give your character a good name is by giving them a normal name.
Sex
Well do you want them to be a boy or a girl? or maybe neither! Maybe they are a Gem so their gender is an illusion. or maybe they are a genderless alien. it's up to you!
Age
Is your character young and filled with life? or are they old and wise?
Race
This bit depends on what universe it is set in. MLP you could have Unicorn, Pegasi, earth pony or Alicorn. Steven Universe you can have human or gem. Harry Potter you have muggle, witch/wizard or a death eater (I think, I don't really know much about the HP fandom :S) Really if you want a believable OC you want to pick an everyday race but sometimes, if you make them well, you can get away with a rarer race!
Weight
Is your character underweight, average or overweight? You could always stick with the stereo type and have a big, jolly, lovable character or a skinny, nerdy, social outcast character. Your choice!
Height
Are they tall? Or are they small? Don't really know what to say here other than make sure their weight and height are compatible. By that I mean if they're skinny they're most likely tall. And vice versa.
Home town
Where were they born? A small mining town on the edge of Canada? A beautiful lake side house in the Himalayas? A town on the outskirts of 18th century London? Chances are their childhood home will be one of the main molds which will shape them into who they will become. My Creepypasta OC, Dr.V was raised by is father in Quabec, Canada until the age of 12 when he was kidnapped and was experimented on for the next 4 years of his life, shaping him into the pale, yellow eyed, tall, socially anxious, childish psychopath he is today. Their hometown is important.
Current location
Hiding in an abandoned warehouse? Constantly on the run? Nice villa in the middle of Spain? Where they live now will add to your characters personality and appearance! If they live in a cave they will most likely be pale and socially awkward. If they live in a fluffy cloud house they will be more excitable and fun. Make sure their current location matches their current occupation. Location, location, location!
Sexual preference
This is quite a big part of your character if you're writing a story or posting to sites like deviant art or even role playing! Deciding if your character is straight, gay, bi or asexual (or others) plays a massive part in their life. One way too decide is by putting your character in different situations and see how they react. for example:
Your character is hanging with their best friend, insert name here, who is of the same sex. After getting onto an awkward conversation about relationships your same sex friend kisses you on the cheek and begins to apologize. How does your character react? Now do the same with the opposite sex. How do they react?
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How to make an OC!
Non-FictionA little guide I am putting together on how to make a good OC!