What is it?
When you're learning the guitar, the fewer barriers there are between thinking about playing and actually picking the thing up, the better. Back in my teaching days, I would always advise students to have a guitar sitting ready, plugged into a practice amp, and good to go whenever you find yourself with a few spare minutes. It’s the same for learners and accomplished players alike - the more convenient the act of practicing is, the more likely we are to actually do it.
