I would like to Clean my Rig/Computer

Is this a laptop or desktop? If this is a desktop then you just need to clean out the fans and heatsinks if dust has accumulated in them really. As for laptops, I can't really help you much more here.

Its a Desktop

You can use a household Vacuum cleaner with a nozzle, just be very careful not to knock things  
Cotton buds/ Q-tips are useful for niggly tight bits
Blow on bits, you can create quite a draft using your own lungs you know  
And the part you should clean most? The dirtiest bits imo.
Moto

The "Dust-off" type of spray can works the best. Other methods wll only serve to damage the components. And yes, you must clean the insides of a desktop computer at least once a year - more often if it is floor mounted.

Where does one clean the most? Everywhere! I had so much lint inside 2 old desktops that I took them to the garage to clean them off. Don't try this cleaning in your bedroom.

You know what's just as effective as a can of compressed air, but waaaay cheaper?
A straw.

I find the PSU gets the most clogged with dust. Take off the fan guard, turn the PSU upside down, carefully poke a straw in and "burst-fire" blow untill all the crap stops coming out. Cover your eyes while doing it. For all other components like fanblades and heatsinks I use a 1 inch paintbrush.

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