Saying that you're a “sociable” person can be a bit of a cliché, especially when what you mean is that you interact well with a variety of personality types. Focus on your interpersonal communication skills, such as listening, empathizing, and problem solving. You should have the opportunity to list these characteristics in the “skills” section of a standard job application. There are many reasons why people tend to succeed professionally as well as socially.
It's no wonder that being so nice is how many professionals end up succeeding quickly in their careers.