[immerlustig]

4 things i find very helpful:

1.practising after a forcefull exhale as mentioned already. no way you are valsalva equalising then.
2. to be sure you have the glottis closed do a very slow exhale through your mouth while constricting your throat more and more. that will cause you to make a rather raspy/choking sound (someone described it as the sound you make when sitting on the bog squeezing hard...)
this exercise makes it easy to get a feeling for what the epiglottis really does and eventually it will be easy to do after a full inhale.
3. when closing your nose with your fingers hold them as low as possible. this will allow your nostrils to balloon out a bit (you can see it and feel it very well). if they are, then air is pushed into the right direction (tubes) and you will equalise. if you accidentally valsalva equalise, there will be no ballooning.
4.the tongue action can also be described as trying to make a k- or g-sound. if you do this with a closed epiglottis it will be a sharp and very short sound. if your glottis is open it will sound like a long continuous sigh (because air is coming from your lungs)