However, either is acceptable - but short trousers are definitely not on. Ties are the most dangerous area, as this is when most choice is afforded. Never wear novelty ties. You are doing neither yourself nor The Simpsons any favours by featuring Homer on your neckwear. If you must wear cartoons then confine these to your boxer shorts and show these to no one.
Jewellery is fine in moderation.
Since you are already wearing a name badge, your name in three inch high gold letters around your neck is somewhat redundant. Also, the spaces between the letters harbour resistant bacteria. I apologise for the brevity of this guide, and there are of course many other do's and don'ts. If you wish to investigate this in greater depth, or worry that your own attire is inappropriate, may I suggest that you consult your clinical supervisor or adviser of studies. If they prove unhelpful try the governing body of your institution.