For Multiple Events:
In your Dashboard (pop out menu), select the Check In button.
For Individual Events:
If it's just for one specific event, select the Check In button underneath the event on your Event Management page.
From there, edit/input the specific Events, Ticket Types, and Products that you want included on the list. Select continue once complete.
To get a list of those who purchased tickets, make sure Tickets has been selected in the top right, and then select Download Will Call Tickets.
To get a list of the products purchased, make sure Products is selected in the top right, and then select Download Will Call Products list.