Use an image hosting site such as imagur, then use the direct link in the little picture of a photo (next to the video icon)
its dead easy …download imagur or ohotobucket, then as above click the link on the image , then the image link n the tool box on here and thats it …..another way is …re size the image to around 800 x 600 and drag and drop it in the reply box…you then have a choice of putting the image in at full size or as an icon …full size is better obviously ….but make sure you re size or it will be too big to drag and drop in hope that helps