When using a seating chart for your ticket sales the event setup will switch to using Price Levels instead of the standard ticket types. If setting up a new event from scratch start by clicking the "Switch to Assigned Seating Mode" button to bring up the Price Level manager.
This will give you the option to select an existing price level, or add a new price level. Price levels are tied to the event they are created in; you can have multiple price levels for an event (i.e. weekday and weekend pricing, regular and special event pricing, etc), but each event will need to have at least 1 unique price level for its ticket sales.
After selecting a price level enter the base price for each chart category. Then, just hit the "Save Price Level" button below the last category to update any changes. This price level will be used for new event times that you create.
Do you need to offer multiple price points per category?
Multiple prices can be offered by clicking the + button next to the category. This will add another name and price field below the original. Enter the name and price for the new option, and hit Save Price Level to complete the change. If you need to delete an additional price point later, just click the red - button and save the price level to remove it from the options.