1) Writing for places that people have actually heard of, preferably national outlets.
2) Making $1 to $3 a word, or between $2,000-$10,000 a story, or between $50,000-$100,000 a year.
3) Developing a name and reputation in the business - known as someone who's a pro and who consistently delivers dazzling work.
4) Getting called regularly by top editors, asking you to do a story, rather than the other way around.
5) Securing a "contributing contract" with a publication or publications, meaning you're guaranteed money whether you write or not. This type of contract is most often a "piece deal," meaning you're scheduled to write a certain amount of pieces over a given year for a certain amount of money - and almost always at a much higher per-word rate than other freelancers.
This is what the career of freelance writer looks at the highest level. But don't let it scare or intimidate you. Simply aspire to get there.