One thing to understand is what a page style is. A page style defines the printable area on a sheet of paper. The main parameters are margins. Margins are “no-print zones” where LO is forbidden to place any text.
Contrary to M$ Word, LO Writer takes header and footer space out of the print area, decreasing available space for text.
As a consequence, if you add your header at the end of your writing task, after having “lovingly” laid out everything, composition will be different, lines being pushed to next page, increasingly more when you advance in your document.
If you want to keep your lay-out (which sounds to me you did it manually with empty paragraphs instead of relying on higher features such as “don’t split paragraph” or automatic page breaks before particular “events” like start of chapter), you must modify your top margin to account for the header line.
As you acknowledge yourself as a “rookie”, you are likely to have only a single page style Default Style.
- Display the style side-pane with
F11
and click on the fourth small icon from the left in its toolbar
-
Default Style should be highlighted, meaning it is the currently applied page style (if another one is highlighted, it is the used one which must be modified)
- Right-click on the name and
Modify
- Go to the
Header
tab
- Note the value of Spacing and Height (you’ll be better off if Autofit Height is unchecked) and add them
- Go to the
Page
tab
- Decrease the Top margin by the sum of the noted value
- Push
OK
This should give a good approximation for the fix. Check the pages before a forced page break (where cumulative effect is at its maximum) to make sure your text is positioned like you want. If this is not satisfactory, adjust the top margin until you get desired result.
Note: in principle, text should be independent of individual position in page and only higher level structuring should be used to compose pages. Remind yourself that LO Writer is not page-oriented (like Scribus or Quark XPress) but text flow-oriented. You must not think in page terms but in paragraphs which can eventually be sync’ed to pages with breaks.
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