Hello Stuart,
Some good info here already.
Hereās something super beneficial Iāve done pretty much from the start, and still do today, very often.
Practice improvising over a one chord vamp. There are countless ones on YT, with varioius rhythms.
Hereās one I use to get you started.
https://youtube.com/playlist?list=PLUgRU1ZOJSOLo0uHZtM7fqWuCO3qQPm9O&si=4BhDQScbPMwsAa2-
I canāt stress just how beneficial this is.
Firstly, it removes all the stress of the chord changes. You want total concentration here on being creative, and becoming musically familiar with your scales, or some new bit of musical knowledge youāve attained ; the added stress of the chord changes is going to interfere with that focus, at least at the start.
In any learning environment, guitar or otherwise, I believe that laser focus on one smaller item is the most efficient way to progress to more complex tasks.
If one canāt relax into improvising over one chord, then one canāt expect much success over a 4 chord progression. Itās too much too soon.
So, you just relax, and concentrate on playing short little melodies over that one chord. Use your currently learned knowledge about scales etc, and play around with the notes, and most importantly, the phrasing and rhythm.
And because you only have one chord, its easier to remember the 3 notes in the chord, and target them.
Put in on a loop for 10 minutes to give yourself time to ease into it.
You will be very surprised at just how musical you can be over one chord: there is infinite variety to be had. And as your knowledge and musical toolbox grows, so do your musical options.
Now Im no expert, but Iāve been at this improv for a little while now. Whenever I learn something new, like a chord voicing, or a cool little pentatonic line, lick, riff etc, I invariably start playing around with it over a one chord vamp. I believe it THE exercise to start with;
itās been a real bedrock for me. Hopefully youāll find the same.
Cheers, Shane