how do i clean my aspire 6920g from dust?

how do i dust this thing, i dont just want to spray air into the vents...i actuly want to open it and clean all of it from dust, since i think this is become a problem with me and heating up and lagging in games. So how do i open this up without breaking it, do i unscrew the bottom?

 

Yeah there should be screws. Be careful with it though. And check if there's a sticker on the bottom that says "your warranty will be voided if opened" or something like that.

What's wrong with spraying air though?

 

The funny thing about the 6920's cooling system is that there's a mesh screen designed to keep dust from getting sucked in by the fan and sticking to it or the heatpipe.
Said screen does the opposite function and gets clogged by all the dust so that no air gets to the fan to be blown on the heatpipe, thus reducing the entire system's efficacy.
Remove the backplate (six screws, that's all), blow some compressed air to clear out the schmutz from the mesh screen, then put it back on. Should be fine.

 

ok that back plate is is like on the bottom bottom left on the laptop, and the battery is on the rtop top right? im kind of scared of opening it :x.

 

wow that mesh screen was so hard to clean...i wish it was like a lil filter that was remoavble..be so much easyer to clean, heck i didnt even get all the dust out of the mesh.