The goal of this post is to help give you a little guidance in selecting a pair of shears.
1) Comfort. Above all, pick a shear that feels like a natural extension of your hand. You might learn to like a shear, but you might not. It's an awful lot of money to spend in the hopes you learn to like the shear.
2) Length. Generally, smaller shears (4.5"-5.5" lengths) provide better control, but you'll need to make more cuts, so it can be harder to get long, straight lines. Long shears (6.0" and up) let you make fewer cuts, making it easier to get longer straight lines, but you lose some accuracy, as well. Ask senior stylists at your salon what they recommend!
3) Quality vs cost. At one point, high quality and a high cost for shears went hand-in-hand. Then shear companies caught on, realizing that stylists who had paid a lot for their shears would assume they're great shears, too. This isn't necessarily the case - now there are lots of really expensive shears that aren' particularly well-made. Here, you'll need to depend on someone you trust. A quality, top-tier sharpener, who works exclusively on sharpening beauty shears is an excellent resource. Pick their brain for the shears THEY like best. Chances are, they can point you toward a great shear that (hopefully) doesn't cost you an arm and a leg.
This will only get you started, of course, but if you have questions, feel free to drop us a line - we'll do everything we can to provide you with honest feedback