Today we're writing about how to hyphenate titles.
The simple rule: Capitalize only the first element unless any subsequent element is a proper noun or adjective.
- Death-defying Feats by Nineteenth-century Tightrope Walkers
- An All-American Girl: How a Non-English-speaking Immigrant Made Good
The more traditional rules:
- Always capitalize the first element.
- Capitalize any subsequent elements unless they are articles, prepositions, coordinating conjunctions (and, but, for, or, nor), or such modifiers as flat or sharp following musical key symbols.
- If the first element is merely a prefix or combining form that could not stand by itself as a word (anti, pre, etc.), do not capitalize the second element unless it is a proper noun or proper adjective.
- Do not capitalize the second element in a hyphenated spelled-out number (twenty-one, etc.).
- Break a rule when it doesn't work (see the last three examples below).
- Under-the-Counter Transactions and Out-of-Fashion Initiatives
- Sugar-and-Spice Stories for Girls and Boys
- Record-Breaking Borrowings from Medium-Sized Libraries
- The E-flat Concerto
- Does E-mail Alter Speech Patterns?
- Talulah's Twenty-first Birthday
- Twenty-First-Century History (first, if lowercased, would look inconsistent here)
- Hand-me-downs and Forget-me-nots (lowercase short and unstressed elements)
- Run-ins and Take-offs (lowercase short and unstressed elements)
Source: Chicago Manual of Style