Kathy:
From a production operational standpoint, make sure your work order documentation is crystal clear about the location of the print, with plenty of highlighted and warning notices around it.
Communication is the key to success. I'd even go as far as bringing everyone that's going to touch this job together into one room (Art, screen room, print crew, print managers, etc.) for a brief two minute meeting about the job, the expectations that the customer has given you, and their role in the correct production for the order. Quiz each person about what needs to be done, and when satisfied that everyone knows their roles - break and print the order.
Make sure you have a spec sheet with an illustration of the image shown where it is to be printed on the shirt.
Do this really for any unique print locations - side prints, hem prints, shoulders, etc.
When the order is successfully printed and the client is happy, make sure you thank everyone on your production team for their part in doing it right. It may not seem like much, but they will remember it and the next time something unique comes your way there's a better chance that they will remember this experience and work harder for you to make that one a success as well.
Good luck!
-M