|AMD processors use the 'middle dot' method. Look here for details:|
Clean both surfaces with a quality rubbing alcohol (high % Isopropel content) and use a 'grain of rice' size dot of compound at the center of your CPU, but follow the direction on the link to be more clear. Too much is as bad or possibly worse than slightly not enough.
Your fan arrangement is not correct. You should have a rear exhaust fan (out) as mandatory. If you have a bottom power supply in your case you have the option of one or two top fans, if used these need to also be exhaust to remove the heat. This should be more than enough but if you like a front fan (low in the front) can be used to blow air directly onto hard drives and graphics card(s) without causing problems. You want the air to FLOW smoothly THROUGH your case from low in the front and up through all of your components and out high in the back. Side fans disrupt this flow so they reduce the overall cooling efficiency. Most people use side fans to blow into the case, but either direction is bad since it breaks up this flow and makes 'dead' spots or 'eddies' in the flow.
Cleaning should be done with a can of Dust Off or similar compressed gas. You should not remove the heat sink unless you need to remove the CPU or fix an issue with the heat sink. Vacuuming is NOT safe since normal metal and plastic vacuum hoses can carry a static charge which is dangerous to your critical components and the hose itself can be dangerous to wires and components as you bump into them or suck them outwards.
You have to be a little bit crazy to keep you from going insane.