In brief: After your ticket types have been created and you wish to make changes to the price, please follow the steps below. If you have not done so already, please refer to HOW TO CREATE A NEW TICKET TYPE for more information.
Go to Events tab to create a template's ticket types.
Select "Edit/Manage" link on the right hand side of the event you would like to edit.
Select the Ticket Types tab on the left hand side of your screen.
Scroll down to your existing ticket types. Locate the Ticket Type you would like to change and click "Edit" in the Manage menu.
Make the changes to any of the fields that require editing and click Save.