Your friend will feel as if you're the person they can come to for inspiration and guidance in life. Your natural spontaneity and enthusiasm will be important to them, and they'll come to you for advice because they know that you understand them so well. They need to establish a direction for themselves, for their future, and you'll help them do that -- and in helping them, you'll define your own life path more clearly.
But this won't (and shouldn't) be based on an idea that you know what's what and where your friend ought to go in their life; it will be much wiser to take the perspective of not knowing and simply following the signposts as they appear. Staying open to opportunities is a big part of this influence, and if you two can help each other do that, some amazing things will result.