There's a couple of things you're going to want to do.
* Make sure that your machine's air vents are clear of any debris or dust
* Open the device up and make sure that the cooling fan is clean actually running
* Ensure that your CPU's surface is clean and has a proper amount of thermal paste.
I did find a guide on how to get into the device to inspect the internals. I'll link it [guide|126317|here|new_window=true], but you'll only need steps 1 - 11. [guide|21499|I'd also attach pictures if you do get the opportunity.|new_window=true]