The queue to take the trams to the Peak can be very long, especially at the end of the day. Make sure to factor in the extra time (including time queuing for your tram ride heading back down).
Aim to arrive at the Peak one hour before sunset. Then start the Circle Hike and gradually experience sunset as you loop back to the view of Hong Kong Bay and Kowloon. Factor in one extra hour for buying tickets and queuing for the Peak Tram (meaning you should set off two hours prior to sunset). Choose a day with good visibility.