I'll be practicing scales for the next few hours, and thought I'd share a little exercise I just made up to train myself not to press the strings any harder than necessary with my fretting hand. It seems like an obvious thing to do, but I've never heard anyone mention it, so thought I'd throw it out there. It's simple: I play each note of the scale about 16 times slowly, deliberately fretting the strings so lightly at first that they buzz. As I continue plucking the same note, I increase the force of my fretting hand *just* until the buzz goes away, and focus like a Jedi on not increasing the pressure one tenth of a foot-ounce more. The goal is to train my muscle memory so that my instinct is to use precisely the minimum force necessary to press each string at each fret. I find it's especially useful to switch back and forth between playing positions that require the least force (light strings, toward the bridge) to positions that require the most force (heavy strings, toward the nut).