How to overclock AMD Phenom II X4 BE? Noobs needs advice...

[Treize]

I have this CPU placed in a ASRock 870 Extreme 3 motherboard cooled by a Coolermaster hyper 212+. PSU is a 600w Corsair Builder Series.
http://3dmark.com/pcm7/341578;jsessi...1gcwtwzvjdpn04

How do I do it?
It is 3.2 GHz but I want to increase this a little just to try it out without blowing the whole damn thing up. I read I can safely overclock it to 4 GHz or something.

Now, how do I do this? And is my cooling enough?
I have a stock 120mm exhaust fan and a cheap 120mm front fan but I can add a second 120mm to the CPU heatsink if needed (and more case fans if needed).


Secondary question:
If I add a second fan to the CPU heatsink where do I connect this one too? To the mobo as a chassis fan, my fan controller (instead of the exhaust fan) or can I use a splitter to connect it together with the other CPU fan?