I attended a presentation by Jane Friedman at the Virginia Romance Writers' meeting. Friedman is a wealth of knowledge about book marketing and the publishing industry. Check out her website, blog, and newsletters. It's well worth your time.
Here's what I learned about author platforms.
1. As a writer, your platform grows out of your body of work. Your website and blog should be the center of this. Also, your website and blog should be on the same website.
2. Use your website, blog, newsletter, and your social media sites to build readership. Your platform is not just your social media sites.
3. Know who your readers are. It shouldn't be "the whole world." You need to be narrow and focused (e.g. cozy mystery readers, romantic suspense, etc.). She described this with a funnel diagram. It's wide at the opening, but you want to narrow it down at the bottom to your specific readers. Those are the folks you need to focus on.
4. Identify authors who are similar to you. Look at their websites, blogs, and Amazon author pages. See how they brand themselves.
5. The key is to build your audience. Readers like interaction and engagement.
6. Plan your give-aways strategically. These should be lead magnets (to generate new leads and new readers). Afterwards, look back to see how successful the contest was.
7. Be patient. It takes a while to grow an audience. Keep writing.
8. Check out Wattpad and Instapoets on Instagram. These are two interesting ways to promote writing.
9. Make sure your posts and newsletters reflect you and your personality. Talk to your readers on a personal level.
10. Make sure your name, tagline, and brand are clear on all your sites. Make sure that your website is linked to all of your social media sites.
11. Friedman suggested that you have a separate page on your website for each book to optimize your SEO (Search Engine Optimization). Make sure you include buy buttons for all key retailers.
12. Make sure your website has a clean presentation. The most important thing should be the biggest and be first. All things on your front page shouldn't be of equal size/importance.
13. It takes time to find the right approach for you. This is a continual process that you'll refine over time.
14. Show up every day and be engaged.
15. Build your body of work.