the recomandad way is to go for hosting plan.
if not you can share your database thrugh FileMaker also.
But you need to setup your router and port forward .
There are other options as well. Two 3rd party developers, SeedCode and 360Works offer a "synch" tool for use in synchonizing your data between a FileMaker Pro file and copies of this data distributed to FM Go users. This frees the user from having a wireless connection to the hosting database, but also creates significant issues for the developer/database manager to make sure that data is properly kept up to date on each device.
AM, please tell me what additional setup my router needs (I have 2 working networks in different locations now) and what do you mean by "port forward"