To get David's, Kevin's or Norman's secret dream sequences spend as much time with them everyday as possibly, check every location to try to locate Kevin since at times he'll be in the bathroom or the gym locker room or shower, those help with his ending, with David make sure he's the one showing you around the post that helps and try to talk to him either in his office, room or gym, and Norman try to meet him in the kitchen frequently and one time in the gym, but Thomas is the easiest to get.
Viewing post in Guide?
In one of the routes it will give you the option for a town map. I believe it is Normans route. It will happen directly after the talk with Eric the express boy. When that town map shows, click "The Town" and do 2 of those events (Restraunt, Bar, or Billards. Doing all 3 will make you go home.) There is an alley directly behind the bar, click that and theres your scene. Another scene that involves the map is "The River". That will net you a CG with a sweaty and very attractive worker.