Use a pic hosting site. I use
www.postimage.com . Easy to upload from your phone or iPad. Once you upload the pic you want to use just click on share then you will have several options presented to post to different sites. Use the link for message boards, click on that link it will say copied. Then come here and tap on your message screen, it will say paste, tap that and the url for the pic will show up. You can then click on preview and it should show your message along with your picture!