Use the following steps. Note: Do not become friends with Eve.

Kill Buck with the fire extinguisher during your training day.
Do not listen to Eve's initial dialogue when she is in the ground floor lobby of the apartments, and do not visit her in the relaxation room.
Progress until you get the safe key from eve's room and both key cards to enter the lower levels.
Go through the lower levels without expending any ammunition.
After leaving the facility, keep moving to the left past the gate. Try to fire your gun once to have Tom reload his clip.
Once you are past the gate and in the woods, you will encounter gangsters. Fire three shots in succession to kill them.
Make your way to the train station and watch the ending.