#1 SEO depends on HIGH relevancy of subject matter among web sites meaning that the googlebot looks at both sites, and assesses a 'weight' to the relevancy of the two sites content. Soooo, let us say that Your Ebook talks about Women's Good Causes(such as this one does @ www.sophiasirius.net) and the focus community blog/site/discussion group has a high MATCH with that topic, the googlebot will accord a strong relationship among those sites. VOILA a high search result.
#2 Placing a 'see my ebook' link in an unrelated site is like rudely interrupting a conversation say, on foodies, with a riposte on politics. People like to be 'heard' and to be considered knowledgeable on a topic. Keep the focus community's needs in your mind before posting anything, and for goodness sake, instead of a link to your book link, draw a 'relevant' excerpt from your book, and place that in context. Placing a 'come to my book ' link is really ineffective but make sure your profile links to the book and suggest that the community investigate the 'source' at that profile page.
#3 Niche marketing is the core of this blog and there are many other ways to blanket the market, and each to their own, but the pass along market is not resident in the warehouse data warehouses of ebooks(amazon, et.al.) so this means that a sampler(see other posting on FreEbooks here) is more effective as word of mouse pass along inside focused affinity groups(marketese for potentially valuable and empathetic readers).
#4 Much of the ebook marketing is what I call 'ME" marketing, a variation on the "I" space of Apple et al, and that tends to be generational and also skewed towards male energey(take) vice female energy (share and give) which exists regardless of being a woman or a man. So, the core issue we recommend it to identify which gender is more likely to gift or share Your ebooks(usually female) and make the 'appeteaser' available for Free sharing as a way to seed the marketplace.
#5 Once there is a pass along value established, be sure to monitor, and respond with enthusiasm, as feedback from the marketplace is one of the most valuable elements of ensuring book success.
Hope this helps a bit.
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