When citing newspapers in Gramps, I’ve opted to treat a newspaper as a single source, and each issue as a volume of that source. This is much like how you would treat multiple volumes of an encyclopedia.
I originally started out treating each issue as a separate source, but realistically I’m not going to have more than one citation per issue. This became messy quickly for me as I had multiple sources for one newspaper, all with the same name. (I added the issue date to each source, but that only made things look worse.)
I much prefer the one source per newspaper, one citation per issue method. For example, The Daily Tribune becomes a single source, and articles from the 1954-01-12 and 1956-03-27 issues are separate citations from this source. If I had two articles from one issue, they would be separate citations.
For the title, I input the name of the newspaper, and for filtering purposes I include the word “Newspaper” in parenthesis. This is useful also for when I export information, as it makes it clear that this source is a newspaper. (This does feel wrong, as it’s not a part of the newspaper title.)
The publication information includes at minimum the name of the newspaper and the city and state where it was or is in print. If I can get more information than this, I include it as well.
For citations, I include the issue date, and the page and column the cited article appears on. Even though it’s redundant to include the date in here (citations have a date field), this is useful for sorting, and for ensuring two citations from the same page and column numbers of different days will have unique names.
(This article refers to Gramps 3.4.1-1.)