To get a bad ending for Tyler, you should be on the chapter where he is later for work. Do these things
1) Get a shower
2) Put on clothes
3) Drink Coffee
4) Start Argument with Sam
Here comes the fun bit. As you put on your coat and go for the door, Sam will ask you to kiss her. Just walk out of the door.
Then when you're at the police station and Jeffery talks to you, you should lose about 5 mental points and it should be game over for Tyler
When you are playing as Lucas in the restaurant's bathroom, follow these steps:
1) Drag the dead body in the middle portable.
2) Go to the working sink and wash the blood off your hands.
3) Dry your hands at the air dryer, right next to the sink.
4) Get the mop, clean up the blood on the floor.
5) Exit the bathroom.
Do not waste your time and try looking out the window, it'll give Lucas more stress.
If you find any food on a chapter then you should eat it if you wish to keep up your mental state
To get a good first chapter do these things
1) Move the dead guys body
2)Sweep the floor
3) Wash your Hands
4) Hide knife (It is by the urinals)
In the main diner area:
5) Put on music
6) Sit and eat and drink
7) Do not talk to police officer
8) Do not attempt to use the phone
Hope this helps if anyone is stuck at getting really good endings
Once you complete the game with an ending that distributes bonus points, watch the entire ending (including credits) again by selecting it from the Chapters menu to receive the bonus points as many times as you need.