Italics

Use italic type to set off titles, foreign words, unvoiced thoughts, and words used as words.
My favorite book is She Wanted to Read.
Schadenfruede means feeling enjoyment from the misfortune of others.
The word purple sounds funny.

Avoid using italics for emphasis because it is as likely to confuse the issue as to clarify it. (All-capital type isn’t a great option for emphasis either. It’s difficult to read and, in the age of e-mail, widely construed as yelling.)

When you want to stress certain words, look for ways to do it with punctuation or sentence structure. Emphasis naturally falls near the beginning and end of a sentence or after strong punctuation marks such as colons and dashes.
avoid:

Remember, you have to live with your decision.
Remember, YOU have to live with your decision.
options:

Remember who has to live with your decision—you do.
Remember: You have to live with your decision.
You have to live with your decision, remember.