I've been dedicated for four years, and haven't seen him yet. Not because I am not open yet, because I am that. But because I am not ready. Satan chooses who he will show himself to, it is an honor.
I know your feeling, why the hell would you trust someone you cannot see nor hear? You don't even know the guy.
Well, you found the JoS...and why do you think that? Because he lead you here. Ask Satan for a sign of who he is, or if he is real. Stay open and listen, you will be amazed when you recieve his signs. They comes in ways only you can perceive, maybe after a day or two. He WILL respond! Trust me. He have helped and guided me in so many ways because he have his faith and believes in me, in all of us!
Follow your gut feelings, and when you decide to dedicate, do it.
Read other people experiences on this group or on JoS. Although, keep in mind all experiences are individual. What you may experience another may not. Just....don't expect anything. When I dedicated I expected the warm and loving energy...I got something completely else. But I understood it was a clear sign from him.