Organize the material into its main points. Put text or graphics on a visual aid to enhance what you say in your presentation and to help guide the audience through your major points. Use one visual aid to convey ONE major point or theme and support it. Changing design or style during a presentation causes a jarring effect upon the viewers. Text size Letters must be huge.
Readability is the key.
Text font Use a plain, easy to read font. Software programs provide many fonts, but very few of them are readable on a visual aid. Use one font per visual aid. Text style Use italic type for titles of complete works only. Never underline text.