I'd definitely recommend taking in photos of the cut you want, so if that means printing of some pictures of my hair from my blog, go ahead! I've had people do that before. Keep in mind that unless your hair has similar curl to mine, cutting it like mine might not result in your hair looking like mine. If your hair is curlier or straighter it'll probably look a bit different. If you do want your hair curlier, I know that perm technology is better than when you'd end up looking like one of the Golden Girls. These days your stylist could probably give you something more similar to natural curls like mine. I've never had any experience with perming, though so that's definitely a question for your stylist.
I cut my own hair, as I've never been to a stylist who knew how to cut curly hair and I've always left the salon with something other than what I had wanted. Since curly hair is very forgiving, I cut my own hair at home, which means I save a lot of dough not having to go to the stylist every time I want a trim or cut! And at least if I screw it up, I didn't pay a ton of money to be disappointed and the only person to blame is myself.
Here are some more specifics on my cut, which you can share with your stylist. I usually have very short layers on top and then a bit longer layers under that, and then so on to blend to whatever length I'm at. So when my hair was super long I had tons of layers at different lengths, but now that my hair is shorter there's only about three layers in it. Because my hair is curly, if I have it all at one length, it starts to get that triangle/pyramid-head look to it, because the volume is bigger at the bottom. Layering with shorter layers distributes the volume throughout my hair instead of having it concentrated at the bottom. It also helps keep my curls nice, because the shorter layers don't have as much hair weighing them down and stretching out the curls. I'd say my shortest layer on top can sometimes be as short as 5-6 inches, next 8-9 inches, next 10-12 inches, and so on. Since I cut my own hair, it's not an exact science, and curly hair is super forgiving. I'm sure it's super wonky, but it's hard to tell with the curls.
I usually cut my hair dry, because then you can actually see how the curl is going to react when you cut it and where it will lay. When you cut wet, you're essentially cutting blind. This works fine for straight hair, because straight hair lays essentially the same way wet and dry, but my hair behaves radically different when it's wet vs. dry. I've never been to a stylist who cuts dry, but I've heard that there are some curly hair stylists out there who will do it!