Note: To use usage fees, you must first enable them. See Enabling Usage Fees.
Go to Administration > Registration Settings > Activities.
Search for and select the activity that you want to enable usage fees for.
On the Activity Functions page, click Change Usage Fee.
To allow usage fees for the activity:
Select Enable Usage Fee for activity.
Select the usage fee that you want to use from the Usage Fee list.
To specify that this usage fee is exempt for trial classes (i.e. when customers are sampling the activity) select Ignore Usage Fee for Trial Class?
Click Submit.