It's not necessary to tell the listener that you are done introducing yourself. If you do feel the need to close your introduction you can use the expression "That's all about me", which has a kind of self-conscious humility about it. Obviously, you are not going to tell everyone everything about you in an introduction. Also, this expression often segues into something meant to engage the listener or reader. You would do that by saying something like, "That's all about me, now I'd love to hear about you."