Basically, you should start to find out what and why is bad. Then create a new, desired, design and find out the steps needed to get there.
Also, the approach may differ if things don't work at all versus everything is in production so you can't really pull equipment without interrupting your users.
Do you have the Aruba knowledge yourself? If not, I would consult a Aruba consulting partner to take these steps.
From the information that you provided, it is not really possible to guide you more specific.