Develop a standard approach to no-shows with proactive reminder scheduling and a straightforward, easy to follow patient procedure to change scheduled visits. A robust cancellation policy, like having to repay for a broken access appointment, will guard the lost access you incur when patients no-show, though the approach to implementing should stress lost opportunity, rather than feel like a punitive process.
The biggest win to prevent preventable lost access due to this wasted availability is confirming with repeated reminders, and making rescheduling/cancellation straightforward at least at the time prior to the scheduled access period.
Practices also need a system to create a waitlist that is readily managed to quickly slot patients into broken appointment times, as well as dedicated staff whose job it is to make that quick filling possible.
This means considering policies such as demanding deposits, booking patients with narrower time windows, making next-day cancellations occur at cost to the patient - but we still need to appreciate patients may need to deal with transit, childcare, and financial restraints with regard to attending, which don't merit punishment but necessitate compassion in maintaining an open practice and treating patients respectfully.