When it comes to making a typeface combination, there are principles and methods, but no absolutes. You can’t apply all these principles or ideas at the same time.
Just browse this list of ideas and see what strikes you as interesting, and then try it!
1. Combine a serif and a sans serif to give “contrast”
The farther apart the typeface styles are, as a generic but not infallible guideline, the more luck you’ll have. Fonts that are too similar look bad together. Go for concord or contrast but avoid the murky, middle ground where all you end up with is conflict. Put Garamond and Sabon together to see what “murky” means. Or try Helvetica and Univers together, which is just as bad.
2. Don’t choose two serifs or two sans serifs
…to create a combination, unless they are radically different in some way.
3. Avoid choosing typefaces from the same categories
…like two Script or two Slabs. You won’t get enough contrast, and will end up with conflict. For instance, Clarendon and Rockwell together is not a good thing at all.
4. Get enough difference in point size
…between the various typefaces to make contrast.
5. Assign distinct roles
…to each typeface and commit to them without variance. For roles and different types og type read Typeface Selection
6. Try finding different typefaces that have similar x-heights and glyph widths
For instance, Futura with Times New Roman just doesn’t work that well because there is too much contrast between x-heights and widths, but in this case, mostly widths. However, if you are going to work with a condensed font, you can overcome this problem because now you’ve gone for an extreme contrast.
7. Find some kind of relationship between the basic shapes
For instance, look to the letter O in upper and lower case. Round letter O’s and taller oval O’s, in general don’t seem to like each other when creating pairs.
8. Contrast the overall weight of the typeface
For instance, Didot and Rockwell look really bad together for many reasons, but one clearly because they both have a heavy presence and just look mad at each other on the same page, at least to my eyes. But a heavy Myriad looks great against the relatively light Minion.
9. Pay close attention to what makes your eyes dart around
If your eyes are unsettled, something is off.
If your eyes rest and your work gives you that peculiar sense of well-being, your work might be done.
10. Create different typographic colours
By colour, I mean the overall tint a block of type has when you squint at it. If both of your type samples with different typefaces blur to about the same colour, try playing with size, line spacing, kerning, or even substituting one typeface for a heavier or lighter one from the same typeface.
11. Look for clever ways to create contrast
Increase the leading or tracking of one face while decreasing the other and see what happens.
12. Using different fonts from the same typeface may also be perfectly suitable
That is why we provided them at the beginning of each font chapter. You might do well with a Helvetica Black for a header and a Helvetica normal for your body.
13. Try using typefaces from the same historical period
This will take a little bit of leg work, but not much.
14. Don’t forget to consider how the italics of each typeface look
You might get a nice match with a bold / normal pair, but then discover that their respective italic fonts have a cat fight right in the middle of your composition. Don’t overlook this in the exploration stage!
15. Fonts that are too disparate may not work at all
…with a large amount of copy, but might work in a logo or strictly minimal text setting.
16. Try your variations with larger and smaller amounts of text
Personalities multiply or get obscured with varying amounts of texts.
17. Study and learn the classic typefaces on their own
Print them out and stare at them at lunch. Once you know them pretty well, then think about how they work with other typefaces. You’ll know much more going in to solve your design problem.
18. Go for a neutral contrast
…where neither font overpowers the other, and they both are content to play different roles without usurping all the attention one way or another. This kind of neutral contrast allows the interior personality of each typeface to speak on its own.
19. Find a combination that you didn’t make that you like and study why it works
The answers for further combinations are likely in there for you to extrapolate. The entire web is at your disposal for this research.
20. Stick with high quality typefaces you know the names of
Many free or cheap typefaces are going to be missing important glyphs, and this will kick you later if you don’t take care of this up front.
21. Stick to two typefaces
…but use the natural fonts within those typefaces. This would give you up to 8 fonts to work with: normal, bold, italic, and bold italic. You could possibly have a third very unique font used in a very limited way, such as in the header of a magazine or logo. But if you require 3 or more fonts to achieve your objective, you might be working too hard at it.
22. If you can’t put your finger on it…
…Just change it. Keep moving, keep iterating. You’ll either find it, or change the font for something else.
23. Change the typeface sizes
At certain point sizes, a font pair might not agree at all, but at a different point size, everything falls into place.
24. Avoid mixing monospaced fonts with proportional fonts
Well, you can try it, but don’t say you weren’t warned. I can’t ever get a combination from those styles to mix well to my eye.
25. Contrast a distinctive header sans with a neutral body serif
It’s easy to get a golden combination when following that recipe.
26. Don’t mix moods
…work with complimentary ones. A light-hearted Gill Sans is not going to play well with an all-business Didot, I would think. Either get two typeface in the same general mood, or get one with some personality and another with a neutral personality.
27. Look for similar proportions
…out of the box, and then set the fonts in distinct roles.
28. Make it obvious
Typeface combination choices need to have clear distinctions in order for a document to be legible. If there is not enough contrast, the visual hierarchy breaks down, and the roles you assign to different fonts won’t be clear.
Break the rules
See what happens. There are no absolutes, and a clever designer can make just about any two typeface combinations work to one degree or another.