We’re probably going to need more information from you. For one thing, terminology in this field is understandably confusing. (Hmm sounds like an oxymoron.) Some people refer to hardware calibration as calibration that involves an actual measurement device, like an i1D2 or a Spyder. And that is differentiated from software calibration which is a means of making a basic profile using software only - with an app like “Adobe Gamma”.
However, what you said about needing to adjust the on-screen buttons and a separate process that involves software - can also be called hardware and software calibration!
The best way to calibrate is to follow the directions that are given in whatever process you are using. Are you using a colorimeter? Which one? This newsletter article gives a good overview of the procedures in calibrating & profiling a monitor:
colorwiki.com/wiki/Printer_t … he_Monitor
Usually, if the native white of your monitor is reasonably close to your aim point (ei: 6500K), you leave the onboard RGB controls at their factory settings, and go through the rest of the procedures to make a profile. This way, the graphics card ends up doing the color adjusting and that seems to give better results. There’s more on how the graphics card works in another newsletter article:
colorwiki.com/wiki/Monitors_ … s.3F.3F.3F
Luminance (brightness) is a different matter. You have to use the onboard controls to manually reduce the brightness of your display down to a level that is suitable for photo editing. And that depends mostly on your ambient lighting situation.