UKGPro

Login to your UKGPro account and navigate to System Configuration > Security > Service Account Administration:
Copy the Customer API Key from under the header and save for a later step.
On the UKGPro Service Account Administration Page, click on "+ add" in the upper right hand side.
Enter in the admin of your UKG Pro account's user name and e-mail. You will need the user name later.
Scroll down under Web Services to enable permissions. Enable "View" role for the "Personnel Integration".
Click Save. Your new password will pop up. Save the password in a secure location.
Now to get REST Endpoint, in your search bar, search for Web Services. Look at any of the "web service endpoint URLs" and copy up through /services. Your end result should look like http://Servicet.ultipro.com.

Visit the Zilla application and login using your admin credentials and then click Add Application in the top right.
A window with a search bar appears, type in UKGPro in the search bar and hit enter. UKGPro app entry will appear at the top of the list, click Add to Applications button to the right.
Fill in the form with appropriate details and then click Add to Applications.
You will have the UKGPro app added into applications tab section, click on it.
A detailed view of UKGPro application appears. Click Sync now in top right corner.
Enable API Integration and fill in the config details collected from the earlier steps.
Click Next and the sync will begin.