Kiama is about 100km south of Sydney on the coast. Extremely easy cliff to find. It is located at the blowhole (major tourist attraction) of Kiama. From the center of Kiama follow signs towards the blowhole or the Kiama Lighthouse (it’s sort of up a hill at the end of the main street through Kiama).
Park at the car park with all the tourists. The cliff is at the entrance to the blowhole. Water is extremely deep. Cliff height about 18 metres (depending on tide). You can also jump into the blowhole itself (about 10m jump), this is a bit more dangerous but pretty safe in calm conditions. There’s a couple of other jumps off to the right of the lighthouse (when you’re facing towards the sea). Cliffs here are about 20m, and again extremely deep ocean. As far as I know cliff jumping here is legal. The lifeguards were ok for people to have a jump