Read and understand the content for the project. Get a feel for what the author is trying to convey. Choose typefaces that represent the mood and context of the text and determine the appropriate target audience.
Understand the classification of a chosen typeface. Knowing its classification and the letterform structure helps you determine its personality and whether the two pairs will work well together.
SERIF: Oldstyle Humanist, Oldstyle Garalde, Transitional, Modern and Slab
SANS SERIF: Grotesque, Neo-Grotesque, Geometric and Humanist
Compare typeface proportions through x-heights and character width for balance. Establish hierarchy and assign each typeface a purpose and limit them to specific size ranges.
Look for similarities within the details of each typeface you’re trying to pair. Aim for rhythm and balance between the two. Compare the stress of the letter ‘O’, their cap heights, ascender height and descender depth. Their personalities should complement each other while providing contrast. Make sure type classifications and personalities don’t clash.