- You should get one of these. Have had it for years, and it's powerful and makes cleaning easy. (link at bottom)
- The best way, if you're comfortable doing so, take everything out of your case, including your motherboard, and get everything clean inside the tower. Then if you took everything out, the dust won't hide in the case while you are blowing out the parts with compressed air. It's usually a good idea to do your thermal paste while you have everything outside the case as well. Be patient, go slow, and make sure you're working in a static free environment (as much as possible. e.g. Keep your hands on your chassis while you work)...