At a car show the other day, I watched this guy start his Mustang and shift his four-speed from neutral into reverse. He did this a couple of times and each time, you could clearly hear the crunch of the reverse gear grinding against the cluster. What it revealed about this guy was how little he cared about his equipment, especially because there's an easy way to avoid mashing those gears together. It's just not cool. The simple trick is, with the engine running, the shifter in neutral, and the clutch out, to push the clutch pedal in and shift into any forward gear like First or Second. This will stop the main shaft from spinning and then allow you to easily nudge the shifter into reverse. This is not necessary on some new manual transmissions like the T-56 because the engineers have graciously put a synchronizer on the reverse gear to save it from ham-fisted guys like the Mustang owner. It's a small thing, but at least you won't announce your ignorance to everyone within earshot every time you shift into reverse.