1) go make an account at photobucket.com
2) upload photos to said account
3) after uploading, in your album looking at the photos, if you scroll over them it should bring up a menu, and there should be an IMG code.. 3rd box in menu down IIRC
4) copy/paste that code into the typing box on a thread or in a new thread, hit post, and it should show!
For signature, you'll have to do steps 1-3, then go to user cp here (left hand corner of menu bar), on the left hand side choose "edit signature", then copy/paste the IMG code there