So, we discussed this a couple of times before. Personally, I don’t see the point in making a plan to learn to play guitar in 21 days, because I feel that you might be setting yourself up for failure. That said, I do acknowledge that it will all come down to your interpretation of what your understanding is regarding “Learning Guitar”. It can mean anything from strumming a couple of chords to becoming Dream Theater’s lead guitarist if Petrucci ever decides to quit his job.
Now before we talk about this in more detail, allow me to at least make one quick point before we cover specifically my proposal on how I would go about if I had to learn guitar in just 21 days.