Think Like Your Customer
Don't think like a customer; think like YOUR customer. You know your audience the minute you build a brand. But having a general idea of who you want to reach with your product/service isn't enough. You (or your team) must continuously LEARN the people your product/service is meant to best serve. And then, continuously serve those same people in ways only YOU know how.
Think of it like being in a relationship that matters to you. You tend to invest your time and energy on those you love. right? And although you love that person, you will never know everything there is to know about that person. This is what makes relationships so beautiful and so unexpected. Well, it's the same with your customers...
And always keep in mind the old retail adage:
"Customers remember the service a lot longer than they remember the price." - Lauren Freedman (E-tailing Group)

Here are a few questions to get you started:
1) What problems are you trying to solve for your customers?
2) How are their problems solved with your product/service? Be specific.
3) Where are they located?*
4) How do you reach them?
5) What do you do to retain them?
* It's important to understand where they live to know where to direct your initiatives, of course. But it goes a lot deeper than that because before you even direct your initiatives to a group of people, you need to understand 'how' they live to know how to build your initiatives in a way that will leads them to respond.