Take public speaking. And don't slide by, ace it.
Use your elective credits to soak up business, finance, marketing, etc. classes.
Start working with web frameworks (django, rails, node) before you graduate.
Hit up those conferences while you can, most offer student discounts. This is a good way to explore the different sectors of the software development world. You can walk around the vendors areas and talk to recruiters at most companies this way, and you can often find engineers who will be happy to kill a few minutes talking about their company culture, etc.
Google Summer of code.
Get involved in open source communities, who always need volunteers. This can be a good segway into getting your hands dirty and contributing.