Enabling Cheat Codes
SWAT 4 has a large number of awesome cheat codes. However, you need to allow the game to read these codes before you can enter them. Since SWAT 4 is an older title, this must be done in a rather old-fashioned (but simple) manner. First, open up the "Swat4.ini" folder. Find "Engine.GameEngine" and change "EnableDevTools=False" to "EnableDevTools=True."
You only have to go through this process once. From now on, you can just press the "~" button and a pop-up window will appear, allowing you to enter the cheat codes with ease. These codes must be re-entered at the beginning of every mission.
Codes
Some codes won't really help you win the game, but they can still be useful and fun. "Behindview1" and "behindview0" will shift the camera to third and first person, respectively.
"Setjumpx" will adjust the height your character can jump---just replace the "x" with the number of your choice (the higher the number, the higher the jump). "Setgravityx" changes the gravitational force---again, replace "x" with the number of your choice. By increasing the jumping ability while decreasing the gravity, you can create a character with some serious jumping skills.
Of course, the most important code is "God." This will put you in God mode and allow you to basically get hit by rockets at point-blank range and sustain no damage whatsoever. If your primary interest is finishing the game as quickly as possible, this is the way to go.
Tips
There are a number of tips that can make gameplay easier. For example, you can increase accuracy by doing one of three things: crouching, firing in short bursts or moving slowly. Since SWAT 4 is more of a tactical shooter than a first-person shooter, accuracy is hugely important.
Grenades can be a useful tool, especially before entering a room, because they can clear the area of enemies. Just make sure you have confirmed there are no innocents in the room before you throw one.
Most weapons are equipped with a flashlight, which can make going through dark areas much easier. And finally, when you blow open a door with C4, suspects behind the door will be momentarily stunned, allowing you to make an arrest without resorting to violence (which will increase your score).