Simple tutorial to add Command Buttons to your Select Customer Screen.
This also will explain how to change the text next to the search box. Default it says Search notice mine says Search Customer
Example:
Create a Custom Entity Screen choose your Ticket Type:
Select Customers for Entity List/Entity Type
Go to your custom screen enter design mode and add the Entity Search widget:
Select your widget rezise it to your desire and then choose settings and do the following:
Now to add command buttons just close design mode, then reopen design mode and add an automation command button widget. You can drag your button to desired location,resize it, etc.
Finally, delete the old Customers entity screen.