Answer:
Secretly pack items you need in a suitcase over a few days before the main part of the plan takes place. (Id, money, meds, clothes, food, phone, charger, etc,)
Plan then find your way out. Best to do this before you head out, so your not scrambling to figure your exit route. Could be a window or quiet door. Would not recommend the garage or front door as those are loud. If window is on second floor, a drop from hanging over the edge is not damaging.
If you want to be sympathetic, leave a note. They'll panic either way.
Hang out at friend's house or something till you wish to take a big leap and leave them forever with no return
