In addition to the other answers, which are wise, it is a good idea to hold about 10% of your assets in precious metals. The metals are a great hedge against inflation and an excellent diversification investment.

Frankly, it depends on what "type" of customers you have.

If you work with the general population and have a recurring sale item (such as a coffee shop, where people can buy coffee more than just once) - it can be a great way to connect, stay in touch, and remind them of your business.

If you're a one-off sale (a home improvement company that offers a lifetime guarantee, for example) - there likely is little value. Think about it, though Facebook has a HUGE audience, are they truly going there to find your product?

There is, however, a HUGE opportunity to connect/network with other professionals that you could network with. This, in my opinion, is the biggest value in your social media efforts.