Are you afraid to use a real person in your life as a blueprint for a character in your fiction? You're not alone--every writer develops this at some point. The problem is, you probably know a lot of people--or have known people earlier in your life--who would make GREAT characters in your stories. So what are you to do?
It's a tough situation. One on hand, you could probably get away with simply taking a person you know and putting them in your story without harm. Chances are, that person you know probably will never read it. But of course there's always that little chance, isn't there? That chance. Maybe--just maybe--that someone you know just so happens to be the type to file a lawsuit.
Why even take the chance? With a few modifications, you can use all of the greatest personalities and traits from people you know without worrying about ever hurting or offending them. More importantly, this trick will also allow you to make your characters even BETTER than the people you know in real life (yes, no matter how great you think your friends are, they can always be a little better).
I'm going to create a character. It's a male, and for the body type I'm going to go with my friend Mike. Mike is fat, but he used to be fatter, and so the skin on his face is a little saggy, his clothes are baggy and his hair is a little thinned. This character needs to be a protagonist, and it just so happens I met a great guy at my local Starbucks who just so happened to be quite the little racist. Lots of things to say about Barack Obama. Obviously, I don't think his racism is "great," but--as a writer--it's absolute gold. I let this guy talk my ears off, because real-life racists are nothing like what you see on TV.
Next, I want this protagonist to be driven by something that readers might accidentally empathize with. I used to know a guy who grew up in a pretty bad neighborhood, and he told a lot of stories about things that happened. More literary gold.
So here's what we have: a fat protagonist who used to be even fatter. He's a racist, and he grew up in a pretty bad neighborhood. This character doesn't exist in real life. Instead, he's an amalgam of a number of different traits and features of people I knew in my life. He's more interesting than any of the people I based him on--from a literary perspective, of course--and he fits a purpose to my story.