Adding images to your emails can help catch the attention of your prospects and illustrate the message in your email -- a picture is worth a thousand words, after all!
To ensure your images are the correct sized when received, they should be resized prior to inserting them in your email templates. There are several free and easy-to-use image resizing websites (here's an example site) and your computer likely has basic image editing software built-in.
Once resized outside of Outreach, follow the steps outlined here to add your image to email templates, snippets, or sequence steps.
Note: The body of a template has to be ~65KB or less. This means your GIF/image has to be small enough so that the images plus the body’s text is under 65KB.