It sounds like you might have a good foundation on the business side so you need to gain some knowledge of the actual "craft" of Business Analysis.

To start, here's what I would recommend:

• Take at least one comprehensive course in business analysis in order to get an idea of what the profession is all about and the common activities, tools, and techniques employed by business analysts;
• Identify an industry/business domain in which you have strong interest or in which you already have experience - consider beginning your BA career in that field;
• Pick up a couple of books on business analysis and begin your learning journey.  Check out: Modern Analyst Bookstore

- Adrian