Just above the message box are three buttons - " topic Tools," "Search this topic," and "Reply" - click on "Reply" and you will get a reply window into which you can type, then click on "Post at the bottom of the reply window to post your reply. If you want to attach a picture you can click on the "Additional Options" link. There is even a "Spell Check" button just to the right of the "Post" button for the fumble fingered!