In a paragraph list, separate each item with a comma or semicolon. End the last item in the list with a period.

Our training will help you to (1) save time, (2) deliver effective

presentations, and (3) increase your personal satisfaction. 

or 

You will be able to (a) design effective visuals; (b) plan,

prepare, and deliver several presentations; and (c) learn

methods for reducing stress. 

In a displayed list, place a period after each item only when one or more of the items is a complete sentence.

Successful speakers convey the following to their audiences:

Knowledge
Experience
Confidence

 

but

To make the most efficient use of your audience's time:

• Know your audience.
• Limit yourself to discussing essential ideas.
• Use ordinary language.