So, you need to use title case, but you need to know what it is and how to do it. Well, that depends on who you ask. No matter which style guide you use, the basic principle is the same: The first word of the title and subtitle are uppercased, and major words have the first letter of the word capitalized. However, each style guide has its own requirements for how to use title case for that style.
Below you will see the guidelines compiled for APA, MLA, and Chicago/Turabian.