Disassemble the laptop
When a desktop PC unit makes noise, we open the cabinet and dust off the fans. They can also be change with those that are quieter. The problem with laptops is that it is very difficult to disassemble. 
Indeed, to access the fans often requires removing several components and of course remember to order them back then. It is possible to do so, but be careful and be very meticulous.
---
In some cases it is possible to access the fan without removing any part, it will block the fan when you use the blower (that prevent it being damaged by turning too fast).
The best is still to reach the ventilator and manually remove the dust with a cotton swab, for example. In this case, remember to unplug the computer.
Most of the standard manufacturer (for example HP) provides online literature with vector graphics demonstrating how to disassemble a particular series of their laptop.
Use an air blower
Another simpler solution but needs to spend money: an air blower. We must find the vents of the computer and pick up the blower to remove dust.
To summarize
- Dusting off a computer can reduce noise and avoid overheating problems.
- For a laptop, access to ventilators is tricky because you have to remove many components.
- It is best to use an air blower that will remove dust through the vents.
