First time OCing

hi guys

This is gonna be my first time Overclocking.
intel core 2 duo E6750(2,66ghz)
Kingston ddr2 2x2gb PC8500 1066 mhz
But my motherboard only reads pc6400 800 mhz
GA-P35 DS3R/S3R rev1.0
Nvidia Geforce 8800 GTS 320mb
and Western Digital 250g and a samsung 300g HD

I've been reading a lot about overclocking everywhere, but I keep ending up here again
I'm too scared to try and screw around myself so I'd like your advice on this.
I read something about keeping your FSB:RAM ratio 1:1 but I don't know how

please treat me like a newbie and explain every term, because I probably won't understand it elseway.