Building Credentials Before Publishing

How have MWSA published members built credentials before their nonfiction works were published?

Background: When I began researching and writing my U.S. Navy submarine-themed book, I realized I needed more credentials, Yes, I'm acknowledgesd Submarine Force civilian family with personal experiences relating to my book. And I'm also both an award-winning newspaper journalist and public relations counselor with extensive writing skills.

But were thse credentials enough? I started writing without pay/and being published in several publications that have bumped up my credentials. I suspect I've spent way too much time doing this.

Questions: responses appreciated:

Now that I've decided to not go the traditional publishing route, how important are my credentials, specifically for nonfiction?

In today's many publishing venus how important are authors' credentials?

If you worked to build your credentials, what advice do you have?

Thanks, Nancy (Subsister)