I'm pretty sure I've made half of the mistakes
in the book and it's a safe bet the other half is on its way.
So, make mistakes?

I do remember reading that mono bit from Taylor on here and it's definitely helped me...
Using buses both for specific effects & tracks and then for CPU workload is pretty convenient, plus it's neater and less cluttered somewhat. I definitely don't use them for everything though.
One thing I used not to do (and realize I should have more often than not) is save different versions the work during the process, step away from it when need be and get back to it with fresh ears. Or listen to the alternate mixes in different settings (the car, living room, while cooking dinner, etc.) I find the different levels of attention and time away from the studio help me gain new perspective, and sometimes something I liked better at first I'll get jaded with easily and something else that seemed dull will shine through.
It also prevents ear fatigue, focusing too intently on the material and EQing endlessly and so on can become taxing. So if I simply try alternate mixes and figure out which one I like better over the course of a few days / weeks, it's much easier to set to work again and bring the mix where I want it.
Monitor off is also a great recommendation. Can't argue there.
I also am particularly fond of listening to every track individually, muting off the complete mix, when everything is piled together your ears easily get fooled it seems and some lesser things get drawn into it without your noticing at 'first glance'. Also toying with muting specific tracks, just leaving two or three combined, etc. Again something I used not to do... and now makes me drop a cumbersome track from the mix more often than not.
I don't really know what I'm doing, but I like to entertain the idea that I learn as I go.