What is the best way to cut a 100% perfectly straight line on a 10 inch long paper without messing it up?We used a rotary-style paper cutter when I was a photographer in the NavyIt was much better than a chopper-styleNice, clean, straight cuts Without running out to buy extra equipment tho\' I would have to say yardstick/razor knife/prayer is your best optionRemember to pray because the knife is very sharp and will likely cut into the straight edge, even one made of aluminum (I\'ve done it), leaving you with a less than perfect cut and a damaged rulerPlus, there\'s the possible slip/jerk/bump/shift factor unless you clamp the stick downI think if you NEED the cut to be 100% perfectly straight, look into a rotary paper cutter.Other related question