A short drive around the dealership can tell you whether you like a car. It may tell you very little about whether you will like living with it.
Plan a route that resembles your normal driving. If you spend most of the week on the highway, include a suitable faster road. If your usual trip involves narrow streets and a tight parking space, spend time turning, reversing, and parking. Discuss the route with the salesperson before leaving.
Give yourself a few minutes in the parked car first. Set the seat and mirrors properly. Reach the controls, look over your shoulder, and see whether the driving position feels natural. A seat that bothers you within ten minutes deserves attention, however much you like the exterior.
Pay attention to the parts you will use every day
While parked, try the climate controls, windows, camera, locks, and other equipment that matters to you. If a feature helped sell you on the car, see it working. Sit in the passenger and rear seats where relevant. Check whether the cargo space accepts the things you actually carry.
On the road, turn the audio down and give yourself time to listen. Notice how the car responds during normal acceleration and braking, whether the steering feels predictable, and whether any vibration or warning light appears. Different vehicles feel different; an unfamiliar sensation is a reason to investigate, not a diagnosis.
There is no need for aggressive braking, abrupt swerving, or testing whether a driver-assistance system will save you. Use ordinary, lawful driving. Anything that requires a more demanding diagnostic test belongs with a qualified technician in appropriate conditions.
When you return, write down what you noticed before the sales conversation takes over. “A clunk during low-speed turns” gives the mechanic something specific to examine. “I didn't like how it drove” is harder to act on.
A test drive also gives you permission to reject a car that appears fine on paper. Poor visibility, awkward controls, or a seat you cannot get comfortable in will still be there after the first month. You are going to spend a lot of time in this vehicle. Use the drive to find out whether you want to.