I am in IC design industry and want to make a switch to business career. What should I do?

The best thing is to let your manager know that this is the direction you want your career to take and obtain his/her advise and assistance.  Your manager will know where the opportunities are and can introduce you to the probable hiring managers (talk to them BEFORE they have openings to find out what it would be like to work in their departments and what they are looking for).  Your manager can also make sure you are enrolled in any in-house classes that might be useful to make you more qualified.

The next most useful thing to do is to enlarge your network of professional contacts, epecially outside your own department.  You can do this by volunteering for committees (for example, special events committees or emergency reaction teams).  Make sure to take the time to get to know the other committee members and stop by to see them once in awhile.  Having contacts outside your own department will help you to expand your knowledge of the organization.