First google result I get for "tor hidden service instructions" is https://www.torproject.org/docs/tor-hidden-service.html.en which explains the two config lines you need to add to create a hidden service
Literally all you have to do is add this into your config file.
HiddenServiceDir /hidden/service/path
HiddenServicePort $EXTERNALPORT $INTERNALIP:$INTERNALPORT
If you're hosting anything at all this shouldn't be even remotely difficult.