How to Capitalize Composition Titles. An excerpt from AP Style, (writing explained.org)
Capitalize the principal words, including prepositions and conjunctions of four or more letters.
Capitalize an article (a, an, the) or words of fewer than four letters if it is the first or last word in the title.
Put quotation marks around the names of all types of works except the Bible and catalogs or reference materials.
Translate a foreign title into an English one unless the specific word is commonly known by its foreign name. However, musical compositions in Slavic languages are always referred to in their English translations.
Classical: quotation marks around the composition’s nicknames but not compositions that are identified by their sequence. For example,
Beethoven’s “New World Symphony,” but Beethoven’s Symphony No. 9.
“To Kill a Mockingbird”
“Of Mice and Men”
“Saving Private Ryan”
“The Dark Knight Rises”
“Stairway to Heaven”
“Call of Duty”
“God of War”
“A Night in the Chinese Opera”
“Nixon in China”
“The Sound of Music”