Go to Calendar and click on a time slot in day or week view or on a day in month view on which you want to schedule a private session (e.g. training or lesson) with the client. On mobile, this is done via +.
You will then see a window where you can directly select the existing client. In addition, you have the option to select the activity, location or trainer and you can schedule multiple sessions (series) with the client. To learn more about how to create a series or recurring schedule, click here.
Please note: you can only schedule a client directly if the session is a private session (private activity). If it concerns for example a group lesson or training, you can click on the session and add clients.