Those random cases are when it’s best to look at what they’re up to after the weekend. "Or when you come back from vacation, and you know that he’s been with you for 10 days, when you get back, that makes those few days more important."
"If you can pretend like you’re not suspicious and pay good attention, you’re better off than if you’re bugging somebody every day with things like, ‘How come you came home at 10:30? I thought you were gonna be home at 9,'" McKeever says.
If the person you’re trying to catch thinks you’re suspicious, they’re going to change up their routine and make it harder for you to tell that something’s up. "Be patient, and pretend like you’re too preoccupied with other things. Playing it cool is definitely better."