Google has a free guide for webmasters called Google’s Search Engine Optimization Starter Guide. The guide is a must read. Below is a summary of the guide.
Title Tags
Title tags are the title of your blog post or page that shows up in Google when someone searches on the keywords that are in your title tag. For example, if someone searched on the phrase search engine optimization, the title of this blog post would show up as a result.
Use short, unique and descriptive title tags. If you’re blog’s theme doesn’t allow you to alter the title tag, you can use the infamous All-In-One-SEO Pack to tweak your title tags.
The Description Meta Tag
Use the “description” meta tag. This provides search engines with a summary of what the page is about and will show up in the search results as a snippet of what the blog post or page is about.
Use unique descriptions of each page. Do not use generic descriptions like, “This is a web page.” Also, don’t duplicate descriptions for multiple pages or posts and don’t copy the whole article into the description meta tag.
If you’re blog’s theme doesn’t allow you to alter the description meta tag, you can use the infamous All-In-One-SEO Pack mentioned above.
URL Structures
Provide a friendly URL. Friendly URLs include the title of the blog post or a shortened version of the blog post title that excludes words like “the”, “of”, “ways”. Use the Clean Slugs plugin that you can get when you subscribe to Joost’s mailing list to shorten URLs to just their keywords.
Use descriptive URLs and not a heavily nested URL scheme like http:/blogname.com/nest1/nest2/nest3/next4, etc. Use lower-case URLs and use www. or not. DO NOT mix URLs preceded by www. and some excluding www. Use the WWW Redirect plugin to help control this.
Site Navigation
Make your blog is easy to navigate. A sitemap of your blog displays the structure of your blog and provides users, as well as search engines, to easily navigate and index your blog.
You can also use “Breadcrumb” navigation which allows your readers to navigate back quickly on your blog as well as view how they landed on a specific page of your blog.
You can use the Google XML Sitemap plugin to help Google understand your blog. Also, provide a helpful 404 page. A 404 page is a “Not Found” page and should be customized to help your readers get back on track at your blog. Provide a link to your home page, your archives page, a sitemap of your site, or useful articles that can be found at your site.
Quality Content
Provide compelling content that visitors will link to. Provide easy to read text and stay organized around the topic. Reduce spelling and grammar errors. Don’t dump huge chunks of unformatted text.
Use paragraphs, subheadings for layout separation. Unique content will continue to bring readers back as well as bring new readers. Provide an original piece of research or break an exciting news story. Create content based around your readers and not search engines. Avoid hiding text. It’s so easy!! 
Anchor Text
Anchor Text is text that describes a link. Write anchor text that describes a link. Avoid writing links with the words “page”, “article”, or “click here”. Don’t use the link’s URL as the text link, for example, http://thisisthelinktouse.
Use short descriptive phrases or a few words in the link. Format links so they are easy to spot and avoid making them look like normal text. Avoid excessive keyword-filled links and make use of internal links so Google can understand your site better.
Heading Tags
Use <h1>, <h2>, etc. appropriately. Usually the title of your blog post will be an <h1> and the only <h1> on the page. Sections of text in your blog post can be separated by <h3> titles, like this blog post. Imagine you’re writing an outline. Use heading tags when it makes sense.
Optimize Images
Optimize your images to include descriptive alt=”" tags. Use unique and descriptive file names for your images. Avoid keyword-stuffing text in alt tags. Simplify the path to your images by placing images in the same folder. WordPress does this by month in the uploads folder. Optimizing your image file names and alt tags will help Google’s Image Search to better understand your images. Use commonly supported image formats like .jpg, .gif, .png, and .bmp.
Conclusion
There’s plenty more to the guide including information about the robots.txt file, the rel=nofollow attribute, and ways to promote your blog. Spend some time reading and understanding Google’s Search Engine Optimization Starter Guide. SEO straight from the horse’s mouth.
