Iain Rob Wright is a horror and suspense writer in the UK. Go here to visit his website. He is a full-time writer with a number of books published, and several are being adapted to screenplays and graphic novels. He was recently interviewed and has some ideas about marketing.
You should do everything you can to be 1) professional and 2) approachable. Set up a decent website, make sure all of your books have great covers, and use social media to get yourself out there (especially to begin with). Use these tools to make sure people can get in touch with you. If someone emails you or reaches out on Facebook, and you respond kindly, you can be sure that that fan will go out and get more people to read your books. Your fans matter, so make sure you show them that. That’s marketing 101 as far as I’m concerned. It’s not enough to want to succeed, you need to make other people want to see you succeed.