According to Statistica, 76% of the U.S. population has at least one social networking profile and by 2020 the number of worldwide users of social media is expected to reach 2.95 billion (650 million of these from China alone). Of the social media platforms, Facebook is by far the most dominant - as of the end of the second quarter of 2018 Facebook had approximately 2.23 billion active users worldwide (Statistica). Mobile devices have become the dominant platform for Facebook usage - 68% of time spent on Facebook originates from mobile devices. Other popular social media platforms for marketing include WhatsApp, WeChat, Instagram, Twitter, LinkedIn, Pinterest, and YouTube.
I prefer simple SEO techniques and ones that can be measured in some way. I have never just wanted to rank for competitive terms; I have always wanted to understand at least some of the reasons why a page ranked for these key phrases. I try to create a good user experience for humans AND search engines. If you make high-quality text content relevant and suitable for both these audiences, you’ll more than likely find success in organic listings and you might not ever need to get into the technical side of things, like redirects and search engine friendly URLs.
The SEO starter guide describes much of what your SEO will do for you. Although you don't need to know this guide well yourself if you're hiring a professional to do the work for you, it is useful to be familiar with these techniques, so that you can be aware if an SEO wants to use a technique that is not recommended or, worse, strongly discouraged.