Typically the review is two phases:
Phase 1
Review and approve the part orientation, datum locations, clamp locations, overall size, and all the other major defining features.
Phase 2
Review the overall design concept, access, functionality, material utilization, and final details for the fixture.
After final design approval, to track changes and ensure good communication throughout the post-design process, an Engineering Change Notification (ECN) is created and submitted for customer approval for any changes in customer parts or models and/or customer-driven changes in scope, cost, or project timelines.