Just thinking about a certain activity can change the shape of your brain. According to this video by ASAP Science, imagining doing an activity actually helps people hone their skills in that particular activity. Granted that people still need to physically do the activity – like for example physically touch and practice with that guitar if you want to get better at playing it – knowing that thinking about playing the guitar helps you with practice is great. As the video puts it, a little imagination doesn’t hurt. Now go imagine doing something, then go do it for real.