I just did this. Click " go advanced" , then you will scroll down a bit to see " manage attachments" ,then click on " choose existing" and it will take you to your pictures files. Find the photo, click on it, and then it will go back to to page where you were before the pictures came up. Click on "upload" then you'll have to go down a bit to " close screen" and then " save changes". The you should see your post with the photo.