Help with Deticated server?

Can anyone help me? I always try to set one up ,but no one can connect. I have full connection. Im not sure what and what not to do. I followed many guides but they sucked. If someone can help me id appreciate it

 

these are very difficult to set up trust me ive accomplished to set one up one a long time ago but it didnt work well...

a few problems i found was that if you have a router it won work
there was a old site started bye some canadians that had a video tutorial but that was a while ago it was dedicated101 or something besides it usually lags and no one likes to join dedicated servers..