Search engines reward you when sites link to yours – they assume that your site must be valuable and you’ll rank higher in search results. And the higher the “rank” of the sites that link to you, the more they count in your own ranking. You want links from popular industry authorities, recognized directories, and reputable companies and organizations.
When I started out, I pitched SEO packages to local business owners that I met through networking, which is a good way to start building result-oriented business case studies that show the ROI (return on investment) that has been generated from your efforts. Once you have those and you can prove you consistently get results, you’ll be completely indispensable because nearly every online business succeeds or fails based on the quality of their digital marketing (and people who are really good at it are rare).
Several customers are turning towards social media to express their appreciation or frustration with brands, product or services. Therefore, marketers can measure the frequency of which customers are discussing their brand and judge how effective their SMM strategies are. In recent studies, 72% of people surveyed expressed that they expected a response to their complaints on Twitter within an hour.
YouTube is another popular avenue; advertisements are done in a way to suit the target audience. The type of language used in the commercials and the ideas used to promote the product reflect the audience's style and taste. Also, the ads on this platform are usually in sync with the content of the video requested, this is another advantage YouTube brings for advertisers. Certain ads are presented with certain videos since the content is relevant. Promotional opportunities such as sponsoring a video is also possible on YouTube, "for example, a user who searches for a YouTube video on dog training may be presented with a sponsored video from a dog toy company in results along with other videos." YouTube also enable publishers to earn money through its YouTube Partner Program. Companies can pay YouTube for a special "channel" which promotes the companies products or services.
Facebook pages are far more detailed than Twitter accounts. They allow a product to provide videos, photos, longer descriptions, and testimonials where followers can comment on the product pages for others to see. Facebook can link back to the product's Twitter page, as well as send out event reminders. As of May 2015, 93% of businesses marketers use Facebook to promote their brand. A study from 2011 attributed 84% of "engagement" or clicks and likes that link back to Facebook advertising. By 2014, Facebook had restricted the content published from business and brand pages. Adjustments in Facebook algorithms have reduced the audience for non-paying business pages (that have at least 500,000 "Likes") from 16% in 2012 down to 2% in February 2014. 
Paid inclusion is a search engine marketing method in itself, but also a tool of search engine optimization, since experts and firms can test out different approaches to improving ranking and see the results often within a couple of days, instead of waiting weeks or months. Knowledge gained this way can be used to optimize other web pages, without paying the search engine company.
Pay-Per-Click (PPC) Advertising: PPC advertising enables you to reach internet users on a number of digital platforms through paid ads. You can setup PPC campaigns on Google, Bing, Linkendin, Twitter, Pinterest, or Facebook and show your ads to people searching for terms related to your products or services. PPC campaigns can segment users based on their demographic characteristics (age, gender etc) or even their particular interests or location. The most popular PPC platforms are Google Ads and Facebook.