If no one knows who you are, then you’re anonymous. Anonymity lacks credibility, thus people won’t trust or care about what you say.
Look at the life of Prophet Muhammad, may peace and blessings be upon him, the #1 most influential person in history as published in Michael Hart’s 1978 book.
Over a millennial ago, he began to invite his people to let go of polytheism and instead worship the One Divine Creator. He first began by asking them all, “If I told you there was an army on the other side of his hill, would you believe me?”
He asked this question to gauge his credibility among his people. They responded, saying that he was truthful and trustworthy.
Credibility comes first, then the message. But, how do you build credibility?
Look at the promotion of books and movies. Popular books almost always have the title of the author bigger than the title of the book.
Movies, almost always have the face and name of the lead actor front and center of the poster. Batman being an exception, Christian Bale doesn’t have as much brand equity as Batman, thus logically, Batman makes the poster.
When promoting something on your own, you can only go as far as your reputation allows. Reaching beyond the scope of your reputation requires the leverage of others’ reputation.
If you don’t have the reputation of others to leverage, then build your own. Make promises and deliver on them consistently over time. This builds trust. Do excellent work with honest evaluation of what you do for others, whether they’re your clients, customers, or employers.
If you’re an organization or company of people, relentlessly engage in public relations.