Question about pointers and skill values

Hey guys, im pretty new to this community, but it seems really nice. :)
I've got problems with translating sometimes (google translate sux) but im handling it for now ;d

So, my questions is how do you find the value of a certain skill, for example, the magician's Mana protective barrier ?

I want to make a skill hack for uk server or gsp :p

What's the method for getting those values?
Also, please reply in english :)

1. Scan type: Unknown initial value → First Scan
2. use another skill than before
3. Scan type: Changed value → Next Scan
4. repeat 2. and 3. until you have the right address