It's very easy for an author to put aspects of their personality in their character and as a result, there's no real emotions between the characters in the story, and the story itself becomes dull and lifeless. So a way to avoid this that I've come to rely on, is to create the characters before beginning your novel or story.

  First start with your characters name, write out the character's full name, first middle and last, however don't use your first name or the name of a previous character, this causes you to subconsciously use the last characters personality and similar traits. If you can't think of anything other than previous characters, look up baby names until you see one fit. 

     Next, create the physical feature of your characters once you've decided on a name. Start from top to bottom beginning with your characters hair, is it abnormal color, such as dyed or natural. Then move down to the shape of his/her eyes, and what color they are, does the character wear contacts? then their bodily features such as weight and height, is the character fat and stocky or do they have a thin and tall build? And finish with their clothes and style. Are they goth or preppy? Do they wear their favorite colors or do they follow trends?

   

     This is the hardest part of the entire process because you have to be as specific as possible and whether, you've written before or are inexperienced it's very easy to make them into your own personality or recreate a previous character as I have mentioned before. Start with the most blunt things about the character, is he/she shy or outgoing? Is she/he mean or nice? Is she/he rude or polite? Simple things that create the outer shell, then once you have the part of the characters that the others are supposed to see first, go deeper into the character, what drives them to be who they are and act the way they act? What are the biggest weaknesses to your character? How does that cause them to make mistakes? Give them habits that relate to their personality and weaknesses. It's also very easy to tie their style into their personality. 

     When you create their backstory you have to tie it into what you've already made, so ask questions like, was it traumatic or pleasant? And how does that affect them today? Are they rich or poor? This would be a little easier considering you completed the last step, it's like working backwards. But you have to make sure that each detail connects to the personality and person that you have already created. Almost like a giant web.