Reach the pump room of the Waystation without alerting any Feeders.
The start of Chapter 9 has you putting a gear in place to ride an elevator down. Once down there, you will open a door to a kitchen where a Feeder enemy will be. It will scamper off. From here on out press to crouch and walk carefully. There are a couple groups of Feeder enemies in the areas next. They cannot see, but they can smell and hear you. Walk slowly and when you see food cans, use kinesis to throw them in another part of the area to distract them. Once you get to the Waystation, you will see a saving icon appear and the achievement will unlock. The amount of time spent sneaking around is really only a couple of minutes. Since it's at the start of the chapter, this becomes extremely easy to do if you missed it.
@4 Yeah. I got a bit impatient and walked around a corner too quickly. Ended up nose to nose with one. It was staring right at me for about 5 seconds. I turned around and kept going. Ding! Achievement Unlocked.
Dont stop and fuck around with TK, just do it all in one go, the only time you should stop walking is when youre waiting for a door to open. Got it first time on my classic run, its abit of a scary one lol