When you log on it should say "new post" on the top right. Click "new post and then type a message with a title. To add pictures there is a little picture next to the spell check button (when you are on the posting page, towards the top right of the window) click that and then browse for the picture that you want (you have to accept the terms that your images won't be pornographic etc. before it will let you upload a picture). Please let me know if there are any questions. When you're done typing your post just click "publish".
Love you all,