Log into your account, and click the client page.
To the left of the button "+ Add new client", select the export button, as illustrated below:
The download file includes a column named 'uid' (i.e. user identifier), a unique number assigned automatically to each pet owner in your Easy Busy Pets system. If you download all the pets using the instructions below, then each row in the pet export file corresponds corresponds to the pet owner's id in the client export. This way you can identify which pet belongs to which owner.
Log into your account, and click the pet page.
To the left of "+ Add a pet", select the export button, as illustrated below.