Submitting a package for RPM Fusion is easy as in Fedora. See also Contributors
Occasionally, packages have any issue. See also ReportingBugs.
Helping others and keeping in contact can be done using email at https://lists.rpmfusion.org/archives/.
There is need to head package review if you are a Fedora package maintainer. See also https://bugzilla.rpmfusion.org/show_bug.cgi?id=2
There are also few infrastructure tasks if you are a sysadmin. See also https://bugzilla.rpmfusion.org/describecomponents.cgi?product=Infrastructure