Every author website should include these elements, whether on the homepage or elsewhere.

1. About/bio page. I recommend a brief, professional bio (250 words or less), and a photo. You can expand in many different ways, but a short bio upfront is very helpful and essential for those looking for the quick facts.
2. Information on your books, products, and services. You might have a separate page for each book or product, or you might combine everything together. Regardless, don’t skimp on the details, and always include links to where your books can be purchased in both print and digital form. Ideal: A downloadable press or media kit for each book.
3. Social media integration. Let readers know where else you’re active online, and make your site easy to share (using social share buttons, like you see on this site).
4. Social proof. If you have notable media coverage, good reviews, positive testimonials, or a significant following on a specific platform (e.g., Twitter), let it be known.
5. E-mail/RSS subscription or sign-up. Make it easy for people to subscribe to your blog via e-mail/RSS (here’s how). If you don’t have a blog, then offer an e-mail newsletter. (Give people a way to stay connected!)

Here are mistakes I often see on author websites:

1. No way to sign up for updates. If people visit your site once, they may not ever return. But that doesn’t mean they aren’t interested in receiving news from you. Always offer an easy way for people to be notified when you have news or content to share.
2. Too many pages or paths. New visitors to your site will not likely visit more than a couple pages of your website. Make it clear on your homepage what’s important by having a clear “call to action.” (What do you most want people to do when they visit?) Don’t build your site for you—build it for your future readers.
3. Heavy images, intro pages, Flash, etc. If your site takes a long time to load, or requires special plug-ins, or doesn’t work on an iPad (Apple does not support Flash), you will lose a chunk of your visitors.
4. No clear contact info. Make it easy for people to e-mail you or find you on social networks. That’s why you have a website, right?
5. Unfriendly to mobile devices. Nearly two-thirds of my new site visitors are on a mobile device. Thankfully, my WordPress theme is mobile-friendly. Is your website mobile friendly? (If you’re using WordPress, all you need to do is install the free plug-in, WP Touch.)

For related posts:

• The Big Mistake of Author Websites and Blogs
• Why You Should Add E-mail Subscription Service to Your Blog
• 3 Numbers That Matter to Your Platform
• Get Started Guide: Blogging for Writers
• Please Don’t Blog Your Book: 4 Reasons Why