Using images in a presentation is common place. But to the dismay of many audiences, they are often misused and actually detract from the overall presentation.
To avoid this misstep here are some best practices for using images in a presentation. Using these tips will help you build professional integrity and motivate your audience instead of confuse them.
Introduction
Whether you are professional speaker or you work in a corporate office, creating a presentation slide decks is common place. When used well, slide decks give you the opportunity to convey your message in a compact and visual way. It connects you with your audience and engages along the story you are telling.
Unfortunately, most slide deck fall woefully short of this ideal. A badly designed slide can negatively impact your message and your ultimate goal, be it a sale or call to action. Poorly selected images are major contributor to flawed design. Using images well can help you overcome badly designed slide decks.
Using Images to Support Your Main Point / Message
Largely, your images should support and emphasize your main points and not detract. Overall, the images, whether photos, icons, or graphics, should contribute to the whole design, look, and feel.
Do
Use images that support and strengthen your message

Don't
Have text heavy slides with zero visuals

High Quality Photos are a Must
Nothing loses the audience’s respect faster than a low-quality, pixelated slide image. Using images that are high-resolution photos is a must not only to help convey your message but establish a sense of authority.
Do
Use quality and high-resolution images

Don't
Use low-resolution, pixelated images

Be Consistent with Image Look & Feel
Your whole presentation needs to focus on a single overarching message or point. Your photos, also, need to reflect that. The easiest way to have consistency is using images from the same photographer. Most photo shoots consist of similar images but with different angles, poses, or scene variation. Visually, your audience is seeing one cohesive message.
Do
Have similar themed images

Don't
Use drastically different images

Avoid Cluttering Slides with Photos
The point of using images is to add visual interest along with supporting your message. Using too many on a slide will distract the audience by forcing them to tune you out while figuring out which photo to look at. Check out my post on Adding Text to Slide Images for more ideas on working with photos and text.
Do
Use a single background image

Don't
Use a photo collage

Choose Photos Over Clipart
Clipart, its quick to find and free to use. However, if you have any recollection of (or cultural reference to) the 1990s, it hasn’t change much at all. It looks cheesy, cartoonish, and dated. In a professional setting, this is not the look you want. Sticking with professional stock images and icons is much better.
Do
Use images to create a polished, professional look

Don't
Use cheesy, cartoonish, and outdated clipart

Maintain Diversity in Photos
Now more than ever representation matters. All media outlets, stock images included, have, for too long, skewed to a certain population group. Lack of diversity in your images will be noticed by your audience.
Using images that celebrate uniqueness and diversity will be appreciated by your audience. However, be careful not to re-enforce stereotypes.
Do
Use images that represent all population groups

Don't
Use images only representing the predominate culture

Finding Quality Images
Doing random image searches on the web can be time consuming. Fortunately, there are several image sites that offer a wide variety of photos. Many are free and public domain. However, always check the usage license before downloading.
- Noun Project Photos: https://thenounproject.com/photos/
- Unsplash: https://www.unsplash.com
- Pixabay: https://www.pixabay.com
- Pexels: https://www.pexels.com
- Raw Pixal: https://www.rawpixal.com
- Flikr: https://www.flickr.com
- 13 Diverse and Free Stock Photo Sites: https://blog.walls.io/socialmedia/diverse-and-free-stock-photo-sites/
Wrap Up
Lastly, your slides need be clear and easy to read. The text should be large and minimal. When using images in your presentation, select ones that support your main points and message. Don't use images just for sake of using them; this causes clutter on the slide.
Be aware of how all of your images work together from slide to slide as well as for the main point on an individual slide. Ensure you are incorporating representation from diverse backgrounds.
In the comments sections, share how you use images in your slide decks and what techniques you use to ensure a high-quality finished product.