Each custom sign has his own set of operations(called box) that are executed when the player interacts with it(right click).
A Box contains 2 list: a requirements list and a rewards list.

If the player meets all the requirements the rewards will be executed..
Also you can set a custom description to each box(shift+right click)

To see a ful list of requirements, rewards, informations, permissions and others; take a look here: https://github.com/xZBasTZx/SuperSign/wiki
if you need help, don't hesitate to ask; discord: Bast#0448