Ruling on the marriage of a woman who has no guardian and no ruler?

Question:
If she has no guardian at all and no ruler?

Answer:
She marries herself. If it is feasible, she should have someone like the head of an Islamic center or similar marry her, as this is more appropriate; because he takes the place of the ruler, as may happen in America and similar places. The heads of Islamic centers are suitable if she asks him to seek a suitable match for her. If that is not feasible, she marries herself out of dire necessity in the presence of two witnesses... "I have married myself to you," or "I have married you for such and such," in the presence of two witnesses and with a bridal gift. She marries herself, taking on both sides of the contract: "I have married myself to you," and "I accepted."
Q: If a Muslim is found, even if he is not a ruler, is it permissible for her to appoint him as her agent?
The Shaykh: It is not obligatory for her to do so, because he is not her guardian. But if she appoints him as her agent, there is nothing wrong with it.