The simplest way to measure a behavior is simply to observe it in its natural environment.

One way to study behavior is simply to ask people what they do. This can either be done in a direct face-to-face interview, or through a survey or questionnaire in which the participants are asked a series of questions about their behaviors.

Sometimes psychologists will devise a task to measure behaviors in the lab This can be a simple scripted event or a computer program/game that the participant can interact with that measures behavior.

Psychologists use specialized tools to measure behavior. For example, a smart watch can track a variety of information such as heart rate, activity, and sleep patterns.