guitars

Find a short/approachable song written by someone else and really learn it. Don't just learn to play it.

What key is it in? Are there key changes? How do the keys relate to each other?

What BPM(s) is it recorded at? Know when you're playing 8th notes at 120 bpm vs 16th notes at 60bpm. Is a certain section actually just a "half time feel" driven by the drums/bass?

How do the chords in the progression relate to the key, how do they relate to each other?

Same as above but with the leads. Which scales are used, and to what effect? Are there maybe some chords over which the root note does NOT sound like the resolution to a phrasing?

Take note of dynamics and how they effect the feel of the piece. Not just noting accents, crescendos, heavy picking, staccato notes etc but the results of how they interact. Think of the bits of Little Wing where the song almost stops, your ears have just a moments break, and then a loud/aggressive bend breaks through the almost-but-not-quite-silence. To the above points, consider what note is being bent to here. It's a D bending up to an E, which is the tonic note of the relative minor of the song.

Johnny Winter has some approachable jams. Stuff like "Life is hard" has some simple change ups but is mostly the same progression.

In some interview or video or maybe a "Riffer Madness" Dime mentioned that the most effective learning tool was paying attention. "Just look and listen" or something like that. Taking that to heart has certainly improved my playing.