When my kids were small, I often heard the phrase, "It takes a village to raise a child." It felt very true and I was very thankful for my circle of supportive moms, especially in the early years. Since then, I have been thinking a village is useful for more than just raising children. I think we need a village for many of our ventures. Artists of all kinds, including writers, need a village for support, exposure, advice, inspiration, and to feel a part of something.
The best way to support any artist is to spread the word, and the easiest way to do this is write a review. Reviews on Amazon or Goodreads boost an author's reputation. Have a bad review? Well, I can tell you that authors don't like them, but they happen. Not everyone likes the same thing;) They still count toward review counts, which is a thing at Amazon.
Along with giving more reviews, I have started tweeting and sharing news of other author's successes. I went through a time when I wasn't having many successes of my own, so it felt good to celebrate others. I made it my job to promote other people's publishing news, and it made me feel more successful. I was more connected to my writing community. It made me believe that anything was possible again.
I went to conferences without the belief that I would be discovered. I went to meet people, make friends, make connections, and maybe learn something in the sessions. You know what? I want to go to more conferences, because I want to see those people again. I want to keep working at those relationships. Not with agents or editors I met (although that would be nice and happens sometimes), but with the other creators.
You might not even realize it. The woman who wrote a middle grade novel about snot who sat next to me in one of the sessions, I voted for your book in the Crystal Kite. Sorry you didn't win, but you had at least one vote.
Celebrating other people who work in your field is working on your own career, even if your career stinks at the moment. You have some good people to rub shoulders with.