PortForward help

hi im new to mikrotik
and i want to forward a port from one PC to the public IP of the mikrotik
the Public ip and private ip are in the same interface
can you help me to do this
example
ip of the pc inside the network : 192.168.0.100
port that i want to forward: 80
to port: 8080

please use search, this question is answered many times
http://forum.mikrotik.com/t/port-forward-on-rb750g-with-dinamic-ip-on-wan/36760/2