I don't do it often but here's a brief bit of marketing advice for new authors.
Lurking is your best friend.
One of the first things a new author does is join different book sites to proclaim their new status in the world of literary achievements. This is excellent. However, one of the biggest mistakes I've seen new authors make is leaping in without first looking to see if the pool is full of water. Or full of sharks.
Every social networking site has groups set up for different subjects. Selecting the groups that focus on your book's subject, theme, or genre is essential and kind of a no-brainer. However, these groups have rules. Don't just start touting your book as the next best thing until you've made yourself familiar with the way the group works. Lurk for a bit. Get to know the members as people instead of potential customers.
I know you're excited, bouncing up and down in your chair as you clutch your precious book between your sweaty little palms. You want to declare your contribution to the world. Relax. I'm not suggesting you say nothing, just hold off mentioning your book. Let the group members know you are a person first, one who cares about other humans. Believe it or not, an opportunity will arise for you to introduce your book to the group. Often, (I'm thinking Goodreads here) group moderators will designate a folder or discussion thread for just such a declaration.
If the bottom line, money and sales rank, is all that matters to you, by all means, be a self-centered fool. It's that much easier to remove you from the group. One unassailable fact of book sales, however, may cause you to rethink that spam plan you have brewing in your fertile little brain. Word of mouth is a powerful tool. If the word going around about you is your inability to adhere to a few rules, readers may not want to waste their money on your book. After all, if you can't follow simple group rules, how many rules of writing did you break?
*Photo was taken by Filip Maljkovic and is in the public domain.