What have you done, or what change have you made to keep posture in mind?
Also interested as someone with a bad neck.
In a nutshell, keep your spine straight, as if a string were attached to your head, pulling you up. Also do exercises that strengthen your back muscles, and core -- to make it easier to avoid slouching. A good physical therapist can really help -- see if your health plan covers it.
Started doing back-strengthening workouts, and try to stand a lot more during the day at work.
Also don't let myself use my phone while walking, as that was a big issue for a while.
Practicing alignment-based hatha yoga has helped me be more mindful of my posture in my daily life.