I uploaded my picture from photo bucket, It took me ages to work out!
When in Message box if you click on the insert image icon and it will show: (img)(img)
If you then go to photobucket, select your picture and click on Direct link which will copy the code which you then insert between (img)(img)
so it will look like (img)http://1234.photobuckey.com/albums/etc(img)
then post!
I hope it sort of makes sense, this is the way I do it but there could be other ways!
Much love, Thankyou and Goodnight