Kuching is considered a non-active city at night, therefore public transportion after 7 pm may be limited to certain locations within Kuching or outside. Taxis are available 24 hours but also limited to those who used to travel at night and have a place to book for oncall taxi or rent a car at reasonable rate. Since all tourist spots in Kuching area is located quite far from one to another, therefore rent a car for convenience, you'll be able to visit more places. Unlike Kuala Lumpur City, Kuching serves without Train, no LRT, no commuter except for Bus/Water taxis (Sampan).
If bus is your mode of transport in Kuching City ..first you need to study the bus route and make sure you know where you are going.
To be honest to visitors...While in Kuching City don't expect nice,cosy,air-condition bus station ..
My experience..If you want to go to Semenggok Wildlife Centre to meet Ritchie and family the Urang Utan.Go early in the morning take bus number K6.Don't take on noon e.g 13:30pm bus from Kuching because you might miss the return bus you go at noon returning is difficult .Go at 07:00am and are just in time to see Ritchie and friends 'The Urang Utan' feeding time that is at 09:00 am everyday.Spend few hours there and return by bus at noon is easier, but not after 04:00pm it might be difficult.
** Ritchie is the oldest urang utan at the wildlife centre in Semenggok.