There will be a filter provided by God. Most likely a timeline bifurcation where those who choose evil stay in the wasteland while those that turn to our Infinite Creator get to see the beautiful brave new world that lies ahead.
Trips checked. You are automatically leaving or staying according to your own inner choice (good or evil) which dictates whether your body will enjoy the higher realms or evaporate if an attempt to enter is made, according to the yet unknown laws of physics.
The exact mechanics of Rapture are unknown, but some say it happens instantly as a single Event. The Event.