To get a picture to show next to you name, an avatar, In your profile, click on "I have my own image", then paste the http: code of your image from photo bucket. Save and it should show. The upload function does not work.
To post a picture in a post, open your picture in photo bucket. Once the pic is open, on the RIGHT side under Image Links, click on the code next to "Image Code". That will copy the code, and it will say IMG with some brackets before and after the http: along with the rest of the link.
Then, you just use the paste function right in a post where you want the picture to show.
It will paste a long gyberish code starting with bracket IMG..yadda, yadda. Press enter to put some space between the picture and the next thing to type.
I can't actually show you what it should say, because it will just show the picture.
Give it a try, it's super easy once you know how.