You really hit the nail on the head. You need to learn how it should sound on your headphones so as to translate properly on various systems. I can't teach you how to mix on a Forum.There's a lot of trial and error.It would be like teaching you to play on this Forum. Can give pointers but you have to do the work.
I've said this before but it's a matter of the content of the mix that makes for proper translation. Think of it as a big soup. Don't tweak each track with EQ etc. individually until you think it sounds good. You need to learn the frequency relationship between instruments.Frequencies add & subtract from each other. If you were making a soup would you but spices on each ingredient until it tastes good,say salt? Of course because after you put all the ingredients into the pot you'd have way to much salt.If your mix has way to much "salt" now what do you do?
So here's an example as it applies to music. The human voice is very much a midrange instrument SO cut some of the midrange on other instruments. It'll clear up that excess midrange sound. Kick Drum & bass. Same thing.Decide which one to cut some of that low end content. Belive me the track may sound off but the MIX will sound right.

John
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