How do I prevent my Satellite from overheating?

Ever since I got my Toshiba Satellite C55-C5241 it keeps overheating. I live in South Carolina and use it outside often so it overheats easily. However lately it has been heating up hotter and faster. Usually after an hour or two it gets too hot to hold or place on my lap so I shut it off. It has never gotten this hot before even after using it hours on end. And it never heats up that quickly either. I know there are quick fixes like put some tray between me and the device but I'm worried this will cause damage to my laptop. How can I prevent or stop this?