Proofreading tip from my former life as a senior engineer then department head. Read your documents in a different form than you prepared them. If you print, print a copy and read before distribution, read it at the printer! If you are paperless, read the document after generating the pdf (or whatever). If all fails, put it away and re-read after lunch/the next day.
The different form helps you see stuff you missed in libre office/word/spreadsheet.