Photos can be posted by uploading them to any of the photo hosting websites (photobucket being one example of such a site, but there are many). They'll give you a link to paste into the picture tab on the advanced reply here, and your photo will be linked into your post. Please limit the maximum pixel count of the largest dimension of the photo to 600, which will probably mean that you must resize the photo, either before you upload it, or within that website.