Take all your images, resize them and optimize them for the search engines.
Resize all of them to their correct size and optimize them for speed. Done correctly it’ll pay for itself because images are normally easy to rank, because nobody has the time to optimize them correctly.
And the way you do this is by making a list of keywords that get good traffic and show buyer intent for your product.
You name the name of the folder you're putting your images in the name of your main keyword.
And you name the images the name of the keyword that best describes the image.
You add alt text targeting the keyword you used in the image name. Good descriptive alt text with the keyword you want to rank for included in the text. Keep in mind that this is the text that shows when the image is loading and when a screen reader describes the image.
This will improve web load times and intern improve Google rankings.
And then optimize your descriptions with a call to action and use the 325 character limit because the idea is to rank the images, get free traffic, and have the site pay for itself.