The UVic Writer's Guide

• the first word
• the last word
• the first word after a colon indicating a subtitle
• the word after a hyphen in a compound word.

Otherwise do not capitalize:

• articles (a an the)
• prepostions (of between under through, etc.)
• conjunctions (and but for, etc,),
• the to in an infinitive.

Here are some examples:

As You Like It

Writing Essays: A Short Guide

Notes on the Preparation of Essays in the Arts and Sciences

The Four-Gated City

Joshua Then and Now

"A Valediction: Of Weeping"

"The Force That Through the Green Fuse Drives the Flower"

But if the title has a deliberately variant use of capitalization, retain it:

"anyone lived in a pretty how town"