To post a fee to an individual family such as as Registration Fee, you can either:
Go to Families > All Families, search for the family and click the Row Menu icon. Then select Post Fee.
Search for the Family by entering their last name (or the first few characters) in the "find a family..." Global Search Field. Locate the row for the family and click on Post Fees (link on far right) or click on the Last Name (link) to open the Family Record.
Select the Make Sale/Post Fees button.
In the Post Fees section, select the Transaction Type such as Registration (Debit) in the Type field.
Select a Category1.
Enter an amount in the Orig Amount field and complete the remaining fields if appropriate (Discount, Session, Student, Class/Event, Note).
Select either the Save Fee or the Save Fee & Pay Now button.