How do you monitor your mix?

I've been looking around online for a specific type of headphone cueing technique, I remember reading about it somewhere before but I cannot find it anywhere! I'm trying to find the proper way to balance my headphone level/mix to accurately represent my cued track levels and volume against that of the master track. If I recall correctly, it goes:

1 set headphone mix all the way to master
2 balance headphone volume with that of master out/booth volume
3 dial headphone mix back to 50% cue/master
4 now your cue track(cue on, pre volume fader) is accurately represented to what it would sound like in the master mix

Every article I'm finding seems to prioritize splitting tracks, separating them for beat matching. Since I can beatmatch two tracks in the same headphone cup, this isn't how I would use my headphones.

I'm looking for the best way to drop a track in at the right volume. I understand that it can be achieved by bringing a track in low and then fading it up, but i want to be able to monitor the track against the master, adjust my levels, estimate it's volume v the volume of the master track, and drop it in as close as I can get it to the perfect level. If anyone knows of any article/thread/youtube video describing how to get these levels just right, please point me there!

Also, how do you use headphones when you mix? Split headphone cueing, or mix cueing like I'm trying to figure out? Does anyone prefer to mix without headphones?