Without more information it's very hard to answer your question. What business are you in? What research have you done to indicate that social media is a good way to attract new customers?

With that being said, the real answer is that you are asking the question to the wrong people. The answers you've received know nothing about your situation so they are taking wild stabs in the dark in an effort to attract your business.

If I were you, I'd start by talking to several dozen of your existing customers and asking them this question "If you were me, how would you go about attracting people like you?" The answer may be social media or it may not.

As a marketing trainee you need to know one thing... and that is that your customers will tell you the answers.