Installation-
Depending on how you want to use these
upload the images to an upload solution of your choosing or place them on your server in a suitable location
Integrate somewhere on your site
upload to server in the desired location e.g public/style_images/your style/ downloadbutton.png
Add to the bottom of your post in the forum
Paste the image code into a post e.g
[img]image url goes here[/img]