Any group of people, can establish a trust, it involves no cost, or formalities but an agreement together that they will operate it in accordance with the principles of New Atlantis. An existing organization can have a meeting of officers who decide that their organization should become a trust.
The trust has its own trustees, citizens who act as the equivalent of company directors to run it. Depending on your country, tax system and legal system, you may decide to register or incorporate your trust in some form.
Your trust can have elected officials or appointed officials based on trustees. They can be paid or unpaid, it is all completely up to you providing that you stick to the principles of it being an honorable trust.
You may, as many do, also decide to devise your own ceremony for new members to the trust or New Atlantis citizens, but this should never embarrass any person or put them at any risk.