[Plugin: User Photo] Need help displaying user photos in posts

Hi there! I’m not really that good when it comes to driving blind which means that since WordPress is new to me, I need some help.

Even though there are some guides on how to add a users photograph to their posts, I am still having troubles.

What exactly do I need to do? Please dumb it down as much as you can.
What files do I need to edit? Where do I need to add the lines and so forth.

Thank you for your time!

Regards, Pete