so this relay will be in series with the fan or any appliance...
Yes, so long as the relay can support the voltage/current of the fan or appliance.
on the positive wires and negative from appliance will directly go to ground.
No, one or the other. Not both. Take a look at just about any schematic that involves a switch and a light.
This should go without saying, but I'll say it anyway. IF YOU ARE NOT 100% COMFORTABLE WITH WHAT YOU ARE DOING WHEN DEALING WITH MAIN LINE VOLTAGE, DON'T DO IT. IF YOU HAVE TO ASK ON A FORUM, YOU ARE PROBABLY NOT COMFORTABLE AND SHOULD STOP CONSULT AN ELECTRICIAN.