First Killer: Baby with mask. Very high health. Slow walking movement but attacks rapidly.
Second Killer: Ginger guy with mustache. Low health. Fast speed (faster than you) but attacks
slowly. (appears after you kill first killer or after a few days.)

TIP: In the begining of the game go to the edge of the map and get the axe and sickle and dispose of them in the water. This will prohibit the first killer from getting a weapon. Though he can still kill you with his fist it's a lot more hard to.

1. Burn him via gasoline in the MIDDLE of the map. So he doesn't douse the flames in the water. After that he may still be alive and just be a burnt body crawling. Throwing something at him then should do the trick. Gasoline can be found in the generator room. Matches are found by the campfire and in a green backpack in one of the rooms.
2. In the building on the far side of the camp with the crate that blocks you way during the first you go in there and get the tool box. You grab the hammer (the second one that falls out) and go to the broken bridge on top. You swing near the bridge to fix it and you cross. You can then pull the crates up but if you let go it will fall. So while one character is holding that switch to another character to stand behind the crate on the building side. This person will lure the killer under the crate and when that happens switch back and let go of the rope by pressing up arrow. This will crush the killer leaving him severly injured.
3. Throwing stuff at him. Certain things that you throw at him can do minor damage. Like the beer box or the bucket.
4. The rake not only stuns him a bit but does a little bit of damage too.
5. Get the golden key by either destroying the sock in the brown backpack (by throwing it) or get nude and have sex in the room with golden key on the wall. Pick up the key and it will automaticly open a door in the two story building that leads to the attic. In the attic there will be an EMPTY shotgun. To get ammo you go to one of the rooms and go through one of the drawers. Two underwear should come out and then a SINGLE shell. Another shell is found in the wooden box in the bunkbed room in the big building. These are the only ones you get so use them wisely. It will do loads of damage to the first killer and an instant kill to the second killer. You can also open the door with the axe.
6. Okay this one is a little hard but it's effective. You know the zipline on the big building? Well when you zipline down it it knocks off the roof mantle. Now if one of the killers is below the roof mantle when it falls it will get an instant kill on both of them. You will not only need to use one of your buddies as bait but have precise timing, VERY precise timing.
7. Now I told you to dispose of the weapons earlier but if you didn't do that you can still use them usefully. Knock down a killer (with a rake or vomit) then start slashing it. NEVER attack a killer with a weapon when they are up, even if they are unequipped.
8. This is more of a trap rather than a way to kill him but it helps. In the kitchen there is rotten food. Eat it and you will vomit. The killers slip on the vomit leaving them stunned for a bit.
9. Once again this is more of a trap. In the bathrooms in there boarded up bathroom there is a teddy bear. You need the axe to break the boards to get in. Take a dump on the toilet and the teddy bear will fall down. If you throw this ONLY at the first killer he will become distracted by it and leave you a chance to run or strike.
10. Turn on the wood chipper and wait for the second killer to come by it. Once he is next to it throw something at him and he will fall in resulting in an instant kill.

Hope this helps :) There may be more that I forgot or haven't found out yet.