Once you've uploaded the pictures on to photobucket, copy and paste the "IMG Code", like your posting a comment/ or starting a thread, push the submit button and that should do it.
Beneath each of your pictures at photobucket is a list of codes, but you have to have the mouse over the picture to see them. Go to the one that says IMG code, and copy it. You should be able to paste that code into a message here and see your picture.