What makes sounds pop out more are that they have their own defined frequency range.2 or more instruments having the same instruments doesn't make your mix muddy,cause in dance music,it's almost impossible to give each sound it's own specific frequencies,although it is possible to give it it's own specific frequency range.
Easiest way,choose a low lead layer,mid layer,and a high and probably a buzzy top lead.Layering the same sort of sounds playing the same notes and then putting a harsh eq on it would not only sound bad,the more you cut,will make it thinner to the ears.So choose layers wisely.
Eq layers separately,and together as a group as well.
Also a cool trick that I use,is after I've dealt with low and muddy frequencies(which I consider to be between 250 to 500Hz).
I use a multiband compressor to balance frequency content.
Also,if you're having trouble eqing correctly,look up for a PITCH FREQUENCY Chart and use them.
How I use the pitch frequency chart is,I put a low cut and enter a frequency value off the chart,depending on key of track,to the low cut.If I think I can cut more,I enter a higher value.If it happens to sound like I've cut too much,I bring the cut down to the last value in key and use shelf.Shelves are the most underrated tools in an eq.Unless you're using it to its extremes,the overall all sound will not be Changed too much,but when you listen to it with the other instruments playing,you'll definitely have made space for sounds in that frequency range.
