Take the BTS Sukhumvit line to the Phra Khanong station.

Exit the station at Exit 3. Walk down the stairs and at street level, complete a U-Turn. Walk straight ahead 340 meters to Sukhumvit Soi 69/1. Turn left into the soi and walk 30 meters to the steps on the left side of the soi.

(Note that Soi 69 are Soi 69/1 are different soi's)