I've started planning a story based in modern times, and the character who's story I will be writing in first person is loosely based on somebody I know - that is, he has similar characteristics, and a dysfunctional family, though I have exaggerated and changed parts of his personality. My problem is this - when writing drafts for sections of the story, I can't envisage anything but my friend, and therefore start writing as if I am him, not my character. Has anybody else had this problem? Can anybody suggest anything I could do to give my character a sense of identity and to disassociate him from my friend? Thanks a lot.
Perhaps write a few drabbles based on the strongest differences between your character and your friend. Maybe give your character an adventure that your friend wouldn't have participated in.
As they say, all writing is rewriting. When you read it back during the edit process, you'll have that difference in mind and should be able to rewrite accordingly, as long as you keep in mind you based that character on your friend. IOW, keep writing. You'll probably come up with how you want to present the character later as you develop him/her. Then when you go back, you can make adjustments to what you wrote before.
I would start looking at other people to include in your character. Just personal opinion, but I don't think we should ever create a character based on only one person we know, mainly because we only see certain aspects of that person. Combining several people gives us more realistic, well-rounded characters.
So very true. Ever wonder why you like someone that other people don't or vice versa? Ever stop to think that the person you know as your mother isn't the same person that others know as their friend or work-pal? None of us ever see the whole of a person and everyone is a different person to different people.
Try selecting a physical image for your character. Doesn't matter who. A drawing or a real person, so long as you don't know him. Stick him in a document with the character's name under it. List out all the character's details that you have worked out under the picture. Every time you write something about the character look at it and try to mentally associate the events with the image and name. At the moment your mind has associated the character with your friend because you don't have an alternative available.
You could change one or more of his important characteristics, probably preferrably a visible one, so you won't think of the real version, but this other, different fictional one. Suggestions: limp, accent, sexuality, hair colour, name, family structure, age. You could also make him greedier, cheerier, more philosophic or more interested in, I don't know, rugby. Whatever makes him different enough for your needs and as interesting as possible to read about. You could also consider merging him with some other person you know (of). That way you can bring together the best (for the needs of the story) of several people and build the evolved Digimon equivalent of an awesome character.