There are traditionally two important numbers you should know by heart: 3200K which is the temperature of tungsten lighting and 5600K which is the temperature of sunlight at midday.
Almost all cameras have the ability to set a custom white balance using a grey card or white card. This is done by filling the frame with something gray or white and pressing the white balance button which zeroes the values so that color neutral.
For much better control, professional cameras also have the ability to dial in a specific number for your white balance. This is great for dialing in your look – if you want more of a warmer tone, push the color temperature higher, more cool, push the temperature lower.