Listen with your eyes closed.
Way back in high school one of my classes was band class, now this was not brass band but strings and wood wind. I was a cello player and very much enjoyed it but when it was time to sign it out to practice at home I had wished I picked the flute....I digress....What does the cello have to do with ham radio? Well back when I was in band class part of our testing was to listen to a recording of an orchestra playing and identify as many individual instruments as we could. Simple with violin, double bass, cello and clarinet. But the Oboe, Bass and E-flat Clarinet, Bassoon, Contrabassoon and then the Viola. Our teacher told us to close our eyes as we listened and it would make things much easier and over time it did.
So you ask again what does this have to do with radio? For the past 6 months I have been on a mission to build up my copy speed of Morse code. I really did not like the code and had to learn it and I say "had too" because when I first went for my ham ticket the code was a requirement. I learned the code back then to later forget it once I obtained my ticket.
I have come full circle to respecting and admiring the skill of Morse code. I worked very hard to learn the code and it's very true if you don't use it you loose it. I had lost it over time but in my mid 50's I started again to learn it and wanted to master it....have not got there yet but the challenge keeps me sharp.
I am focusing on contest Morse code and my next challenge will be a higher speed QSO Morse code. I am at the point now (35-38 wpm contest code) that as my practice contest code programs spill the code at me I find myself typing the letter or number and looking at the screen on the PC to see if it's correct and then listen for the next letter. At 36-38 wpm looking at the letter to confirm is not an option I end up missing letters and not getting the call sign or exchange correct.
Now at this speed of code I strongly recommend proper home row touch keyboarding and not hunt and peck the letters and numbers. As mentioned in a past post thank goodness in school I took typing and am able to touch type. As I struggled to hit the 35-38 wpm mark I remembered my music teacher...."close your eyes and listen" I did just that and my rate of copy went from 70% up to the 90's. I don't keep my eyes closed all the time and I feel it's just really helping me to concentrate on the rhythm of the letters and numbers.
To close your eyes and listen sure does the trick for me.