Check out point 2 & 3 on this link. It’s advisable to embed images from another site such as http://www.photobucket.com so that they are esier to view. You’ll find not many people will bother to open the links to your images…as convenient as this is!
Highlight the URL and then click on the IMG box above when you’re composing your message. It’ll bound the url with {URL} {/URL} but a [ instead of {. Ideally you would want to resize to 800 pixels on the largest side to make it better to view.