Active Directory Authentication

We are running ltm version 11.3.0 Build 3144.0 Hotfix HF8. I'm looking for a good way to setup active directory authentication to all of our LTM's. We have users that are in a lot of different OU's but all part of the same AD group. What is the proper way to setup AD authentication for all of those users? Also is there a way to set it up with out using a service account? Just trying to figure out the best way to do this.