No one else cant connect

So i have my own host etc. I can even use my own ip if i wanted correct? Well setting up the server works just fine! Great tutorial easy to follow. But making it public seems way to hard. Ive changed the I.P.s and things in other guides like said but when i try to connect to my server it says its down. Also after i somehow host it, will whatever I.P. i use work with the Launcher provided? Of course after i change the settings.