There are 2 ways to approve bookings:

The Scheduling tab shows the next 30 days of bookings under "Submitted bookings." You can approve bookings directly from this page. 

Scheduling Tab > Submitted bookings > Approve, Decline, or Edit. 

While clients are able to book further out than 30 days, we don't want to overwhelm a kitchen manager if they have numerous clients making recurring bookings. To approve bookings beyond the next 30 days, use option 2:

You can approve bookings months out by going to your Scheduling Tab > Select the calendar you want to approve bookings on. 

Once there, any booking that is the color of your "Booking Request" color (typically red) requires your approval. To approve, simply click on the booking and Approve, Decline, or Edit.

Tip: If a client is booking months in advance, it is helpful if they let you know this (and on which calendar), so you know to look for their bookings. 

If you wish, you can set specific Clients to "auto-approve" when they create bookings, so you don't have to manually approve each of their bookings.