In Dan Gookin鈥檚聽Word 2016 for Dummies ( affiliate disclosure; Wiley, 2016), he provides a good deal of helpful guidance for beginning Word users. One particularly helpful resource that may be of interest more broadly is his nicely condensed presentation of prefix keys for producing diacritical marks (pg. 256, reproduced below). ...
Overlining is comparatively straightforward in Apache OpenOffice and LibreOffice. But, for Microsoft Word users, overlining still isn鈥檛 a default formatting feature, as is its companion underlining. Sometimes inserting a symbol or special character聽will work if you can find one that matches the overlined character you need. In other cases, Word鈥檚 cache of symbols and special characters simply isn鈥檛 large enough to cover everything (e.g., when discussing聽nomina sacra). Sometimes, creating a character image might work, but inserting an image can create issues with text flow and line spacing. ...