General Naming
When naming a package you can take some cues from the name of the upstream tarball, project name from which this software came, and what has been used for this package by other distributions/packagers in the past. Do not just blindly follow those examples, however, as package names should strive to be consistent within Fedora more than consistent between distros. You should generally use lowercase and turn underscores into dashes unless there's a compelling reason to follow a different upstream convention.
Additionally, it is possible that the upstream name does not fall into the Common Character Set . If this is the case, refer to: When Upstream Naming is outside of the specified character set .
Also remember to check whether the type of package you are packaging has specific rules for naming. Font packages and the various sorts of addon packages, for instance.