Beyond working on recall, using a secure field and keeping the dog on a lead while the problem is worked on, I know that it can be hard to think of anything else to do.
To make matters worse, if your client's dog has a high prey drive, you might find that things get worse and worse in spite of your best attempts to help.
Make sure that you are giving the BEST advice to your clients with high prey drive dogs by getting these worksheets - they are THE BEST template to have at your fingertips for prey drive.
Let me help you to easily structure your training with your client. Drop me your email address and I'll send you a couple of worksheets to get you on the right track to helping your clients.