Inspect the effect of your favourite EQs have on the sound using a spectrum analyzer. It is easy to get tricked by the curve that you see on the interface of the EQ. Sometimes it’s not an accurate description of what is really going on.
I find it particularly useful to know how the low cut/high cut filters of an EQ perform exactly. There are some plugins that show a steep curve on the visual interface but in reality the cut is much more gradual. This sucks when you need to apply a steep cut and make sure nothing is going on below it.
So set up different EQs on the same channel, load up a spectrum analyzer and see how they perform against each other.
Mixing becomes easier once you have come to know and trust your EQs!