How do I get Latin Modern font?

The best place to get Latin Modern is from the website of the group that created and maintains it, called GUST. The group and its site are in Poland, and the home page is http://www.gust.org.pl/.

If you'll be writing only your equations in Latin Modern (and the rest of your document in other fonts), you need only Latin Modern Math. You can download that from http://www.gust.org.pl/projects/e-foundry/lm-math/download. The file you get is named latin-modern-math-1959.zip.

• Save that zip file in any convenient folder and double-click it to open the zip file.
• Inside it are two folders named doc and otf.
• Open the otf folder, which contains one file named latinmodern-math.otf.
• Right-click that file and click Install in the menu. You may be prompted for an administrator password. The installer copies the font to the C:\Windows\Fonts folder, which makes it available to all Windows programs, including Word.
• Start Word and press Alt+= to insert an equation control.
• On the Equation Tools | Design tab of the ribbon, click the small arrow in the bottom right corner of the Tools group to open the Equation Options dialog.
• Open the dropdown labeled "Default font for math regions" and change the selection from Cambria Math to Latin Modern Math, then click OK.

The doc folder contains files of instructions and samples.

If you also want to use Latin Modern for non-equation text, go to http://www.gust.org.pl/projects/e-foundry/latin-modern/download and click the link that includes the words "OTF files". That downloads the file lm2.004otf.zip  (the number may be different if a later version becomes current). When you open that zip file, you'll see 72 files that compose three families of fonts: lmmono (Latin Modern Monospaced), lmroman (Latin Modern Roman, probably the only one you need), and lmsans (Latin Modern Sans Serif). Right-click any of the ones you want to use and click Install as above.

If you're using Latin Modern Math for regular text, its line spacing does look very tight. Most fonts add "leading" of about 20% of the nominal font size, so for example the baseline-to-baseline distance for 10 pt text is about 12 pt. In Latin Modern Math the leading appears to be less than 10%.

Instead of an exact amount, you can set the line spacing to Multiple, but use a larger value such as 1.2 lines (Word's default is 1.08 lines). If you modify the Normal style to that setting in documents that use Latin Modern Math for regular text, most of the other body styles will inherit that setting. If you do this a lot, it would be best to create another template, using modified styles, to base those documents instead of Normal.dotm.