Yes is the short answer. Any time you are planing on generating money, you should have a plan. No plan means no real focus. There may be some 1/1000 percent of a chance you will succeed, but I haven't met them yet. If you have already started and have generated an income, record how. Doing so will give you material for use in expanding your business faster.
In the case of viral marketing, "viral" refers to something that spreads quickly and widely across its audience. Viral marketing is a deliberate enterprise, though the distribution of a message happens organically. As such, social media provides the perfect ecosystem for viral marketing, though it has its roots in traditional word-of-mouth marketing. While the practice was much more widely used in the early to mid-2000s, as new internet businesses were being created in extreme numbers, it is still common among internet-based business-to-consumer (B-to-C) companies. The widespread adoption of social networks, including YouTube, Twitter, Instagram, Snapchat and Facebook, has enabled modern viral marketing efforts and increased their efficacy.