Hold the infrared thermometer at the appropriate distance from the concrete. For every inch of distance from the thermometer to the concrete, the thermometer will cover a 6-inch circle.
Aim an infrared thermometer at the center of the area of concrete of which you need a temperature reading. This type of thermometer measures the temperature of an area rather than a specific point, so it is important to aim near the middle.
Press the trigger button on the thermometer to get your reading. Many infrared thermometers give a reading within a second or two.
Monitor the temperature of the concrete throughout the curing process, which can take a couple of days depending on the size of your project.