Why, yesh, I do. Twelve of them.
First of all, have the right tool for the job at hand. There's more about that in this post.
So let's assume you have the correct scissors in hand for what you are cutting. Here are some tips for excellence in scissor craft! I sound a bit like Dolores Umbridge when I say that.
First a few prep-work tips:
1) Seems a no-brainer but seriously, have some good light on hand. Daylight is the ideal, but of course many of us have to wait until evening to make stuff because of the small (or big) people at our house who expect to be cared for, fed, educated, played with, etc... Good task lighting is a huge help.
2) If you are tracing a shape to cut out, it is important to trace with a thin, precision line. For instance, cutting along a line made with a fine point pencil will give a better result than cutting along a fat marker line.
3) Getting a nice sharp line on felt or fabric is sometimes a challenge. Whenever possible, I trace the shape on the wrong side so I can use a permanent thin marker/gel pen that is clearly visible and won't disappear or bleed. As much as I love the disappearing purple markers, the lines fade quickly, so I only use them when I need to. I avoid using the blue water soluble markers, because even though they don't fade, which is nice, you have to blot with water to get rid of them and that adds an extra step. Fine point chalk pencils and markers are a nice option for tracing on darker colors and the chalk brushes off. (Never trace on the right side of the felt/fabric with a permanent pen or marker, because even after cutting it will leave unsightly inky bits on the edge of your shape.)
4) Another great way to accurately cut a shape on fabric or felt* is to use freezer paper.
*I mean wool felt. Don't try this with acrylic felt - 1) it might melt 2) freezer paper doesn't stick to it very well.
First, trace the shape on the dull side of freezer paper. Iron it shiny side down to the right side of the felt/fabric.
Then carefully cut around your traced outline.
After you are done cutting, the freezer paper peels off easily. It leaves no trace and your shape will have a nice clean edge.
6) If the scissors are in your right hand, your left hand will actually be doing most of the finesse work. Did you hear that? That's right. The hand that is not holding the scissors is the key to neat, accurate cutting. Think of your scissors hand as the brawn, and your free hand as the brains of the operation. As you cut, keep your scissors hand cutting away from you without turning. Your other hand should be busy rotating the paper (or felt) in a smooth motion to meet the blades of the scissors. The smoother this motion is, the better your cutting will be. Vary the speeds you rotate to maintain accuracy. For instance, the tighter the curve is, the slower your free hand will be rotating the paper.
8) Don't attempt to cut out a complex shape all the way around in one direction, without repositioning the scissors. Most things I cut out are cut from all kinds of different approaches in order to get the very best result. I save the tricky parts for last, repositioning my scissors to get the best angle at each part.
9) If you want cleanly cut interior angles, you can't cut down into the angle then back out of it. The best way to tackle those is to go down one side and end the cut on the point, being careful not to cut beyond the point. Then reposition and cut down the other side, slowly cutting toward the point until the wedge of paper falls away and you have a perfectly clean interior point. Don't be tempted to cut almost to the point, then pluck the wedge of paper out by hand. That just leaves an untidy hanging chad. Which are bad during elections and also in paper cutting.
10) Don't cut directly towards a rounded shape at a right angle. Cut obliquely towards it instead, so that you come in at a shallow angle and go on from there.
11) If the shape you are cutting has interior pieces to cut out (like the inside counter of the letter A or a donut hole), you'd typically want to cut those first before you cut the outer line. On paper this is best done using an Xacto knife on a cutting mat. I also do that to felt if the cutout is small.
To cut out an interior shape with scissors, fold the fabric together so the cut away area is on the fold. Make a snip with your scissors. Unfold and insert the scissors blade in the hole and cut your way toward the line of the interior shape, going on from there.
12) To get a nice continous zig zag or scallop pattern when cutting with pinking or scallop shears, there're a couple of things to watch for. Never completely close the shears as you are cutting as this sometimes adds a deeper cut at the end. Also, when you reopen the shears to continue, be careful to reseat the opened scissors with a scallop (or point) inside the last one you cut before you continue. This will prevent getting half scallops and half points, which detract from the uniform look.
So those are a few of the methods I used to get nice, clean edges and accurate cutting by hand. I hope they are helpful to you!