Everyone has a personal brand, whether they know it or not. Your personal brand is what you put out into the world - your values, your style, your personality. It's what you're known for as a person. If your coworkers get upset because you don't work as hard as they do...sorry, that's part of your personal brand. If it's important to you to have a spic-and-span house for visitors, then congrats, being a good housekeeper is part of your personal brand.
If you're a business owner, then you get yelled at from all directions of the internet about how you need to establish a brand for your BUSINESS, too. I'm not talking about designing a logo, people. Push your visuals to the backburner for a moment. I'm talking about what your business stands for. Why it exists, what values it focuses on, the specific GOOD that it puts out into the world. Every move you make in your business gives your potential clients information about what's important to your business.
If you are a solopreneur or a freelancer, chances are, you are the face of your business. You post as your business/you, you tweet as your business/you, you comment on others' posts as your business/you, you "selfiegram" as your business/you. It's really easy to see how closely tied your personal brand and your business brand can get, but as a business owner, you need to make sure to lay some ground rules for yourself to create a little distinction.
Here are just a few of the areas you should think about when deciding what to share and what not to share as your business entity: