Go to the "Registration" section of your event and choose "Price Tiers" to go to your Price Tier Overview. On this screen you can see all of your price tiers which you can drag-and-drop to reorder how they appear on your registration form.
In the top-right is the option to "Add Price Tier", click this option to customize your new price tier.
Below "Price Tier Details" is the "Promo Code" section:
The "Promo Code" Section allows you to set up a code which will be required to choose this price tier. Click the toggle option to the right, when the option is enabled you will be required to enter the code exactly how you want your registrants to enter it.
When your registrants enter the code correctly they will get a message letting them know:
And the Hidden Price Tier will appear:
The section at the bottom of the "New Price Tier" page controls the availability of the price tier.
Set the "From" and "To" dates and time for when your price tier will be available.
**If the price tier has a promo code, the code can only be used between these dates.
**If you ever want to quickly turn off your price tier, there is a "Disable Price Tier" toggle at the bottom of the page.
Make sure to "Save" at the bottom-right of the page!