I'm using a pair of Samsung S24B420's connected to a 2014 mac mini (via 1 HDMI -> DVI adapter and a DisplayPort -> DVI adapter).
I'm pretty sure I'm just using the default color profiles that mac OS auto-detected, without any other manual calibration on the OS side.
On the screen side, all I'd done until reading your comment here was adjusting brightness and contrast until it "looked nice", but I now realise the screen actually has 3 options for its gamma settings which according to this page equate to:
Mode 1: 2.2
Mode 2: 2.0
Mode 3: 2.4
I've been running Mode 1, but I now I realise I have no idea if this is optimal or not, or how to tell the OS which is selected (if that's even required)!