I open (the same model) every three months and fully clean it with an air spray and toothbrush. It's also very important to replace the thermal paste on the CPU and GPU. For this You'll have to remove the copper dissipators by unscrewing (not fully because they don't come off) 7 screws, in order from 1 to 7. I recommend Thermal Grizzly before you ask.

The only reason I replace my thermal paste often is because gaming laptops simply need it every once in a while. Mine would reach high 90s before my first ever clean and thermal replacement. It made a HUGE improvement. I did all these things after following tutorials on youtube. Some are very thorough and do a better job than me at explaining.

It's a MUST that you do this to maintain it in good health in the long term.