By far the most common complaint I hear from authors, especially those who go the indie route, is, “I have no clue about marketing!” A close second is, “I have no money to spend on marketing!”
Here are two things you can do that won’t cost more than time and effort:
Reach out to book clubs and offer to attend their meetings (or call in) if they select your book
A great way to find book clubs is to create a free account on meetup.com. Using keywords, you can search for appropriate groups either near where you live or across the country. Each group has a “contact the organizer” button, so get in touch! Every book club I’ve attended has been thrilled for the chance to meet a real live author. (While your humble self may think it’s not a big deal that you wrote a book, for most avid readers it is a big deal!)
Look up alumni chapters of your alma mater and ask to be featured in their newsletters
To find local chapters, go to the national alumni page of your college or university–you’d be amazed at how many there are, even for tiny schools. Many of those groups have a monthly or quarterly electronic newsletter and are thirsty for interesting content about fellow alums. (This is another reason why having a brief and compelling description, cover art, and a professional headshot are so important. And if you have a website they can link to, even better!)
Note: Many college alumni chapters also have a book club, so be sure to ask if they do. Your book may not be a fit for the makeup of the group, but you never know.
For the above campaigns I strongly recommend tracking your efforts on a spreadsheet. If the only record of your outreach is the outbox of your email program, following up is going to be difficult. Now start pitching!