Jewellery is a collection that you can use to plump up your tradeshow booth. Some can be customised and some can be sold "as is". I have picked items that have proven very popular at my shows. I find that presentation is everything and you should customise your display cards in a style that suits your personal brand. I like to offer 'something for everyone'. Having people in your booth with lots of things to look at is a great start. It never fails that the more people we have looking, the more stop to see what we are all about.
Pinterest or Etsy are incredible sources for ideas. Good luck!