Go to as shown above.
If you register an adult payer and a child you start with the payer (parent). That way you will save a few clicks.
If this person was also the participant (ie adult activities) you go directly to 'How do I register a customer for an activity?' in its own FAQ. If the participant is a child you continue below.
Next register the participant for an activity. Go to 'How do I register a customer for an activity?' in its own FAQ.