What is the easiest way to find a bat?

I'm curious, what is the most efficient method for locating a bat? With the vast array of habitats and environments they inhabit, it seems like a daunting task. Is there a particular time of day that bats are more active, perhaps making them easier to spot? Or is there a specific tool or device that aids in their detection? Could utilizing a bat detector, which amplifies their echolocation calls, provide a clear advantage? Additionally, are there any known bat colonies or roosting areas in my local area that I should target for observation? I'm eager to learn the best approach to finding a bat in a safe and responsible manner.