- Capitalize the first and the last word.
- Capitalize nouns, pronouns, adjectives, verbs, adverbs, and subordinate conjunctions.
- Lowercase articles (a, an, the), coordinating conjunctions, and prepositions.
- Lowercase the "to" in an infinitive (I want to play guitar).
Paraphrased from The Chicago Manual of Style
: 16 ed. paragraph 8.155
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