Rollplay is something your style, whoever you wanna be, whatever you wanna be. It's not strctly necessary to do like people, but if you want the tips, I have something to suggest. I don't use the same way of course, yet still.
1. If you want yourself to be that part of your chractr, think of your character in the world. What do you wanna see yourself being in that world, and how. Background story isn't that important, but if you want one, think of your happy past and remake somthing that suits tthe word you're in. You won't forget it for sure.
2. If you want someone, or the character you like to walk that earth, simply make a story out of him/her. The personality is something you should take a look. Choose something that's not far from yourself, or whatever you think you can do, or your character can be. In fact, your charcter can b anything, depds on what roll you set him to be.
Why do ghost hunters have to hunt ghosts? Well, there's a fear of being ghosted out there. They may need therapy as well as their ghost hunting kit.