How to enable Remote API for Ubuntu 14.04?

I can´t reach my Remote API for version 1.11.2 and API version 1.23.
Already tried to to change configuration in /etc/default/docker and /etc/init/docker.conf with -H tcp:// but nothing worked so far.
Do you have any suggestions how to solve?

If you use systemctl - try this manual.

systemctl not working for me, because 14.04 BUT solved it by manually starting daemon with “docker daemon -H tcp:// -H unix:///var/run/docker.sock &”.

So daemon is available through sock and tcp.