Jethro's Braindump

Copy Editing

series comma
always use the Oxford comma (or series comma)
only comma
use the only comma, where the subject is one of its kind: e.g. His son, Juliet… where Juliet is the only son
that vs which
use that without a comma, where the information presented is important, and which without a comma, where removing such information would do no harm.

References