I love to shoot at long range. As others have said, form is paramount for consistent shooting as the shots get longer. Keys to work on are a solid, fixed anchor, consistent drawlength, and a strong follow through. It doesn't matter what aiming technique you use. Without the form to direct the arrow to the correct spot no amount of gapping, burning a hole, or whatever will help. At 60 yards short drawing a half-inch will drop you off the target completely. Peeking, plucking, dropping the arm... all will ruin an otherwise perfectly aimed shot.
Now, if you are at the point where your form is solid enough to make 50-60 yard shots it would be beneficial to learn some type of aiming technique. I know that there are people who can simply point and shoot at long ranges but developing a system for aiming will benefit most people. If you don't know your point on distance yet that is the first thing to figure out. Once you know that it is simply a matter of trial and error to figure out holds at long distances. For example, I shoot a recurve off a simple flipper rest. My point on is app. 58 yards. At 50 my tip is about 1 foot below the target, 55 tip is at the bottom of the ten ring on a 3D, 60 I'm just above the ten ring, 65 the arm on my rest is about 8 inches below the bull, 70 the arm is just above the bull, and at 80 the shelf of my bow is right in line with the bullseye. I know where to hold so that eliminates the guess work of aiming and allows me to focus on shot execution.
As CJ said, belief that your goals are attainable is very important. If you only hope to hit the target you will miss more often. Confidence that you can crush a target at 50-60 will enable you to hit with frequency. One other thing I learned is to not be timid with your shot. Trying to be too careful and specific will produce weak shots. Come up, draw, set your hold, and finish the shot strong.
Chris