thick,straight hair--how should cut it???

hey my hair is thick and straight and sometimes it gets pretty poofy unless i sleep on it. its not completely straight though, it either curls in or out at the bottoms.it never goes just straight. my hair is a little below my shoulders rite now and i want to grow it out long but i need a trim now because i have bad split ends. is there a kind of hair cut i can get that won`t make my hair so poofy and will make it look thinner ? shoudl i thin my hair out? what do they do whn theythin your hair out? i was thinking about getting my hair cut like diana from dream, would that work for my hair?

WOW! I have the same hair, too! I hate it, it is so thick i cannot even wear it down. It also is frizzy and big. Tomorrow is my haircut appointment at 1pm, I am getting it layered, but I am really worried. I don`t know how it will turn out. I have heard good and bad things about getting it layered, so I guess I will have to see how it turns out. My hair is also a couple inches past my shoulders. I have tried FX straightening gel, well my hair is a little wavy, but also straight. It worked so good, but you have to put it in, then blow dry your hair. The blow drying will not make it damaged or frizzy with the straightening gel in it. When I used it it made my hair a whole lot less thick, and it looked good. I do not want to do that every night. So I thought maybe layering is a solution. You would not believe how thick my hair is, I haven`t seen many with thicker then mine.
Well hope all of us solve our problems, I also wish I had beautiful, thin hair.