It would be interesting to see experiments that try to pry back the lid a bit on the line between conscious and the subconscious and the communication therein.
They must be out there.
But it's pretty obvious to me that consciousness would not exist if it was not useful.
One way it would be useful if unconcious mind made an automated decision and then ran it through conscious mind to ensure that it was a correct one.
While you can develop actions and skills to the point where you can do them without needing almost any conscious input, it just seems ridiculous to say there's no control from the conscious part of the mind and it's just an illusion...
If all it took to be a musician was conscious will, then I’d be able to play the guitar, instead of constantly procrastinating.
Most people do not really believe that the subconscious impacts our decisions. They may even theoretically say they do, but in practice their executive function believes it decided the decisions that were really done subconsciously.
Ironically, if you believe that you are making the decisions, you cannot override them, and then you are actually not making the decisions.
The key to free will is to really understand that you do not have it.
It just appeared to me that this question is something that interests you, so I wanted to point you to a direction that I have found helpful.
The general process, which appears to be common to various approaches, is to practice specific kind of meditation long enough that you start to see your automatic reactions to the sub-consciously made decisions to slow down, so you are in a way creating room for something before the immediate reaction, and then you can verify the truth in what I describe by yourself. So there is no need to believe what I say or nothing directly actionable that I can transmit through this medium that would be helpful to you.
Few books I have found interesting on the subject: Gallwey: Inner Game of Tennis, Ouspensky: In Search of the Miraculous, Nicoll: Psychological Commentaries on the Teaching of Gurdjieff and Ouspensky
More like your subconscious is making decisions, talking with your mouth, moving your hands, etc... Then you have your consciousness (your "real" self). The subconscious makes him feel and think like he is in control so he (you, your "real" self) doesn't freak out.
But he (the subconscious guy) has the real power and control.