Communication is important to make sure that there is no disconnect between what the client expects and what you’re doing. If you show up on location and some of the details are different than you expected, call your client to let them know and to clarify expectations. The faster you communicate any concerns the sooner issues can be resolved.
There are a lot of moving parts to any given assignment that require logistical coordination. As the moment of the shoot approaches, and especially during the assignment, communication should flow freely and often between photographer and client to help prevent misunderstandings.