One of the essential skills of an audio engineer is the ability to decide "how" to listen to something. Pretty much like a musician, who has to develop the ability to listen to himself/herself and, in the meanwhile, decide how to adjust his/her playing according to what is going on in the music, an audio engineer should be able to mentally dive into the finest details of sound and, at discretion, observe everything from a general perspective.In order to acquire an unbiased ability to do so, a certain amount of constant training is required.Music is a constant emotional state so the idea of developing the "skill" to take emotional distance from it is sometimes rejected by the aspiring engineer who looks at this surgeon-like approach like something to be avoided or better left to audio geeks. In fact, it's quite the opposite.Aural abilities like these will make you a better musician in the first place and a more accurate player but, at the same time, you will be able to apply these skills to your own recordings thus increasing their emotional impact on the listener!You do not actually need to spend too much time doing these exercises in order to improve, as long as you train constantly.Before each mastering session, I always spend no more than 5 minutes doing these exercises with Pink Noise in order to warm up for the session. Occasionally, when I sit down to ear-train, I like to go for more extended periods of time but I rarely hit more than 30 minutes. Past a certain threshold, It is simply not beneficial any more.When practising, try not to exceed 5 minutes per session and practice each exercise with pink noise first and then using one or more songs you know very well. Also, watch your volume! Practice at the lowest possible volume at which you feel comfortable. You can use good speakers or, in alternative, a set of quality headphones (which I recommend for this kind of training).Make sure you practice the exercises in sequence.Some exercises will require you to use the multitrack libraries found at http://www.cambridge-mt.com/ms-mtk.htm (an incredibly valuable resource for students and pro's of all levels) where all downloads are offered free of charge for educational purposes but you can apply the same exercises to the songs you prefer of course. Also, I recommend you visit the mixes discussion sections where you can take a listen to the users' different mix versions of the same tracks. You will hear how different some of them sound and this gives you valuable info about how different people are when it comes to sound perception.When you feel confident enough, import al the tracks in your favorite DAW and start experimenting with EQ. Try to create space for each element using only EQ based on the arrangement, role of the instrument and so on.Follow the instructions as given in each description and most importantly, have fun while practicing! You will improve much faster and for good.Quotes:"The most important thing I look for in a musician is whether he knows how to listen." Duke Ellington"I don't believe in geniuses, I believe in hard work" Michel Petrucciani.