In my opinion, LibreOffice grids -- defaults (Writer/Calc) help page at file:///usr/lib/libreoffice/help/en-US/text/shared/optionen/01050100.html?DbPAR=SHARED#bm_id3147226 , is unsatisfactory way too short. I suggest to 1. Integrate EarnestAl answer at https://ask.libreoffice.org/t/creating-dot-grid-paper-in-writer/69539 , even as is, within the help page for grids -- defaults (Writer/Calc). Or copy his answer as an example section, or a comment section. With the Sample DotGrid.odt provided by that answer to download. 2. EarnestAl statement about the default grid is quite faint is a misnomer. It can not be observed, unless one knows it is there. Change his statement when copying to reflect that.
Quoting the 2nd part of comment 1: 2. EarnestAl statement about the default grid is quite faint is a misnomer. It can not be observed, unless one knows it is there. Change his statement when copying to reflect that. As of this writing, I can not reproduce the fact that it can not be seen. It could be I did something wrong, and was confused. It is quite faint. I still think the 1st part, about integrating EarnestAl answer, is close to a must.
The help for the grid in the quoted help page is to "Specify the settings for the configurable grid on your document pages. This grid helps you determine the exact position of your objects. You can also set this grid in line with the "magnetic" snap grid." It is not to create a dotted line, as it will not be printed. The solution proposed in the Ask service is better suited for a FAQ wiki page.