Use free test patterns or a built-in utility in Windows or Mac OS X to calibrate your monitor. Before calibration, turn the monitor on, and allow it to warm up for about 30 minutes. Ensure it is running at its native resolution.
Using free test patterns is the easiest and fastest way to calibrate a monitor. Stare at some test patterns and use the monitor’s onscreen resolution display or on-screen display controls to alter the brightness, contrast, color levels, color temperature and sharpness. For computers without OSD controls, use the built-in calibration utility in Windows or Mac OS X.
On Windows, go to the Control Panel. Click on Calibrate Display Color under Display. A window opens featuring the Display Color Calibration tool that guides you through various basic image settings. The tool also allows comparison between the current and the previous settings. If satisfied with the new settings, click Finish.
On a Mac, open System Preferences. In the Display section, click on the Color tab, then the Calibrate button to open the Display Calibrator Assistant. The assistant guides you through the calibration process and then produces a calibrated color profile. Check the box Expert Mode to access five test patterns to adjust the monitor settings. When you finish, name your profile and click Done. The new profile appears on the Color tab under Display in the System Preferences.