The cardboard display busts are much lighter weight than the necklaces they are displaying. You need to weigh them down with something to prevent them toppling over. I use those metal cage like things which they sell at Joann's Fabrics, they are really to be used to put glasses or silverware in for picnics. If you turn them over, they have a series of parallel metal rods and you can just put the "leg" of the jewelry bust in them for support. They are verdi gris finish and found in the garden section of the store.
Other than that, how did you do at your first show? I hope you did well saleswise and had a good time, too.
Patti