Check out this very complete (and very useful) type specimen testing template [sheet] from Type Heist: https://typeheist.co/blog/type-testing-template/
This is the template I use to test all Typeheist fonts. As I added more and more characters and multi-linguals, I needed an easy way to test my typefaces without recreating the same thing each time (or worse – different, inconsistent things each time).
This came to my attention this year by the hands of the group of Inês L., Bruno B. and Cristiana (soon I’ll be able to post there their amazing results).
Whether you decide on using this template, or create your own remember to use the most complex combinations. Usually, this might imply using specific dummy text —check out Miguel Sousa’s Adhesion Text*. Or better yet, using real text — try using something from Wikipedia, with real language issues such as diacritics, punctuation, majuscules, etc.
And remember to create a PDF with the embedded font to print it. I reccomend using the Adobe Reader for the best printing results.
This also means checking the “everything is allowed (installable mode in Fontlab) and exporting in High Quality Print. Indesign might not give you the best results when sending the font data to the printer (why?), and of course, avoid converting to outlines!…
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