Keep Vents Clean to Help Airflow

The biggest enemy of a computer is heat.  Computers have multiple fans to protect them against heat, and all computers have triggers that will cause an instant shut down if the computer gets too hot.  (Older computers did not have these built-in safeguards.  They would keep running until the computer became too damaged to work anymore.)

Dust is a computer's second-biggest enemy.  While dust alone can not do much harm to a computer, it can work with heat to kill your computer even faster.  A layer of dust can insulate heat against your components, keeping the heat away from the fans that will push warm air out.  It can also clog up fans or vents, reducing their functionality.  Keeping dust out of your computer is important.

To get rid of dust, I simply use a can of compressed air.  These are available just about anywhere electronics are sold (Walmart, Meijer, Best Buy, etc.) for a few dollars.  If you have not cleaned the dust out of your computer in a while, you may want to take it outside to clean it so that you do not blow all the dust back into your house.

On a desktop, remove the side cover if you can figure out how to do so (it is usually held in place with a couple screws on the back).  Using the can of compressed air, blow all dust out of the case.  Then go to each external vent and blow the dust out of each vent.  (Note:  If your computer is under warranty, I do not recommend opening the case.  Opening the case, even to remove dust, may void the warranty, and many manufacturers are including stickers or sensors to detect if the case has been opened.)

Since a laptop is much harder to take apart, it will also be more difficult to clean.  However, you can still clear dust out of all the vents.  Many laptops have some covers on the bottom that can be removed for easy access to certain components that are easy to upgrade.  If your laptop has these, take them off and blow any dust out of these areas, as well.

Finally, most laptops have a keyboard that is fairly easy to remove.  If you are feeling ambitious, you can unscrew the keyboard screws, flip the keyboard over, and have access to blow dust off of some of the components on top.  However, when you unscrew the keyboard, be careful that you do not unlatch the ribbon cable from the motherboard.  Many of these are difficult to get back into place, especially if you do not have experience at replacing them.

On phones and tablets, just do the best you can.  Many do not have vents, and some do not even have a removable cover to access the battery.  You may or may not be able to blow out any dust on these devices, but the lack of access also means that dust will have a more difficult time getting in.