The color of your images is affected by your light source, be it bright sunlight, shade, tungsten, florescent, time of year (winter produces cooler images, summer produces warmer images). Not all images are created alike and your light source will have a huge impact on their color. The nice thing about your DSLR is that you can set your white balance to produce the best color in your images so that you don't have to struggle with getting proper skins tones, etc. in editing after your shoot.
"Cloud" White Balance
You can use auto white balance, and your camera will do its best to produce the correct color, but let me tell you, it likely struggles with photos in the shade. Many of my shots are taken using the "cloud" white balance. It produces much better skin tones than auto white balance in situations such as indoors when using natural light through a window, outdoors when shooting in the shade (which I often do), and when shooting in the bright sun when my subject/group has it's back to the sun. Again, a strategy I use OFTEN. I would say that over 90% of my images are shot in the "cloud" white balance mode. When I don't use this setting, my photos are cooler/bluer, which I don't really like. I aim for true, warm skin tones!
Your camera may be different, so you'll just have to try it to see how it performs for you. But do try "cloud." You may end up LOVING what it does for your images.
"Auto" White Balance for Indoor Weddings
When shooting indoors in a low-light setting (with very little natural light), I test the different white balance modes to see which works best. My 5D usually works best in "auto white balance mode" in churches, but it's always best to do a few test shots in different modes to see what you're getting.
Underexpose Shots in Direct, Bright Sunlight
This past weekend I shot a wedding and a number of the shots were in bright sunlight. I often use aperture priority when I have to shoot quickly and don't want to fool around with too many settings. So, I popped my camera into "Sunlight" white balance and then set my exposure compensation down 2/3. Sorry if I'm getting into too much detail here, but check out your exposure compensation to see how it works for you. I knew the photos were in bright sunlight and I did NOT want over exposures, but rather rich colors (reason for underexposing the shots). If you shoot in manual mode, you'll bring down exposure by increasing your f/stop or shudder speed or decrease your ISO.
Okay, so lots of info and I trust I'm not being too technical. I hope you can learn the terms and experiment tons with your digital camera. It's all those little tweaks you do outside of auto mode that will produce professional images.
