The purpose of your slides are to enhance what you are already telling the audience.
Your audience will be distracted by anything they have to read. Limit words to only those that will engage them in what you are saying.
Choose san-serif font at 18pt or larger.
Use high contrast colors.
Dark lettering on a white background or white lettering on a dark background are the easiest to read.
Only use images that you are going to discuss or that support what you are saying.
Avoid multiple images on a page.
Use a pointer only when necessary.
Don't include clip art, word art, or animations.
Graphics should be easily read and understood by your audience with little to no explanation.
If the graphic has too much information, consider cropping or blurring what is not needed. If necessary, recreate tables and charts that are easier to read.