No need to be scared. I did it the first time more than a year ago when most of the info on the CSSU page did not make anym sense to me and yet I managed without a hitch. I've done it at least 3 more times since then, always without any problem.

PS
While you are at it, you may as well go for CSSU-Thumb. It should give you an additional boost by using slightly less RAM.