Well, writers are not rich unless they are Stephen King or J.K Rowling. And if you look at their stories, you will see how long it took for them to get where they are.
I never solely depended on my writing to keep me afloat. I've always had businesses on the side. I am currently studying for my Real Estate license and that's what I'm going to do, while continuing my writing on the side.
I would suggest you look directly at the markets you want to write for and skip the middle guys, ask for their writer's guidelines, get familiar with their sites or magazines and send them a sample of your work.
Also, you may want to invest in Writers' Market book. The new one is coming up in 2014, so I'd wait for the new edition but go to your local library, see if they have a 2013 or earlier and go through that. Lots of jobs there. Also, check out the Children's Market, for children's books. There are jobs there and not just for book writing, for magazines, which I've found to be profitable through illustrations, which I do.
Finally, get a Writer's resume ready. You'll need one. No need to add your last job unless it's related to freelance writing work like copy editing, proofreading, research, etc.