PCL stick gauge. Had one in my pocket for more than 50 years, and while the previous ones were lost, stolen or mislaid, the one I currently have is around 30 years old and still accurate enough to confidently set pressures and know they'll be right.
Calibration is the key. I have a PCL tyre inflator that I have calibrated regularly (once a year) and then cross check my tyre (stick) gauges with. Amazing how far out some of them can be! When they are, they go in the bin.