Originally Posted by: Douglas ShowalterA wise man once told me "anything you can hum, you can play." This meaning if you can recognize the pitch (as in singing it back correctly), you can than try and find where that pitch is on the your instrument. We all share the same notes, so have fun and work to better your skills at singing the notes on your guitar and I guarantee you will see results.
To add to Doug's hum method: What helped me without realizing it right away was that for no reason I can ever recall, after I would tune my guitar, I would strike each open string note and kind of sing the note name (ie - E, A,D, G, B and E). I don't know why I ever started that but I still pretty much do it. I think it help drive the note in to my head.
There isn't really magic to knowing how to use the ear, it's a matter of finding how your brain literally makes a connection of the sound, to the note name to the place that note is made on the guitar.
Once I realized I did this and it actually did something for me, I picked a couple of key/frequent notes to do this with (example - 6th string open G or a 5th string barred E at the 7th fret etc).
I had a pretty good ear for what sounded right and wrong but honestly, there were guys way better than me to pick apart a cover song. I never felt overly skilled at it.
The only other thing I can think of that made it a challenge for me to learn by ear is that I think I would often pre-decide how something was played. Instead of sitting down and letting my ear be the driver, my analytical head always wanted to figure out the pattern first. Moral: Don't overthink it. I would guess that's why your ten year old doesn't struggle with it.