My Camera is a Canon EOS Rebel XTi 400 D

How do you adjust the ISO? The camera needs to be set to manual settings. Then push in the button that says ISO. By doing this the different ISO settings pop up 100, 200, 400, 800, or 1600 by using the arrow keys the ISO can be chosen.
ISO Speed /Normal (No flash)
100/200=Sunny outdoors
400/800=Overcast skies, evening
1600=Night or dark indoors

How do you adjust white balance? The camera has to be in manual setting mode. Next, push (WB) for white balance. From there different options are given, they are daylight, shade, cloudy, Tungsten light, White florescent lights, flash, and custom. The custom white balance is also explained which can give you better accuracy if needed.

How do you set exposure compensation? This feature can be used when taking a picture of something black or white like clothing. The white may turn out darker or the black may turn out lighter therefore you would want to set the exposure compensation. To do that put the camera in manual mode the push in the AV+- button on the right hand side of the LCD screen. While holding the AV+- in use the dial on the front of the camera to change from brighter to darker.

How do you set file size and compression? Set the camera to basic mode and select the menu button. Select tab one and hit set, quality then is selected and you push set again. From there you can choose the quality of you pictures = file size and compression.

How do you set the exposure meter mode? By pressing the bottom that reminds me of an eye the meter mode pops up. From there you use the right and left keys to select the desired metering mode. Then you push the shutter button half way down and the selected metering mode will display on the LCD screen.

How do you set macro focusing? I would chose automatic setting of the tulip, unless I had a macro lens.

How do you set the flash mode? The flash will be on as long as you are taking picture in the automatic modes. To turn it off push the lightening bolt. The flash-sync speed can be set in the specialized modes. The red eye can also be adjusted by choosing the menu button and either turns on or off the red eye. FE lock can be used when precise flash exposure is wanted for a particular area of the subject,