Our computers accumulate dirt and dust over the years especially if it is places where it is prone to such. Keeping your computer clean will help to prolong its lifespan and to somehow reduce its wear and tear. Dirty computer is also one of the most common reasons on why the computer itself is running slow and having problems most of the time.
One of the most important things that you should consider is the warranty of your computer. If it is indicated that you should not open the computer so that you may be able to keep the warranty, do not open the computer. Check with the vendor if maintenance is included in the warranty. If it is included in the warranty, bring your computer to the store where you bought it and let the professionals take care of the cleaning. It is better to be sure than to be regretful in the end.
If in case that you are allowed to open the casing, observe proper procedures on how to open it to make sure that you will not damage any component while opening it. Usually, there is an instruction on how to properly open the system unit's casing on the manual itself. So make sure that you check the manual first for safety purposes.
Do not use brushes to clean the inside of your computer. You might damage some of the hardware inside. It is recommended that you use compressed air to carefully and safely blow off dust and dirt from the computers inside. You also have to consider the static electricity that your body has. If you need to disassemble the system unit, it is recommended that you wear anti-static strap to ensure that your static charge will not cause damage to the computer's components.