Default MT3g Cyanogen 4.2.8 And Adding swap

Hellos first of thanks for all your great info, this forum is huge haha, But yeah im kinda newb at this cell phone stuff lol i dont need a dummies guide but ya just did this yesterday still trying to absorb all this stuff.

What:
US Tmobile - MT3g /w Cyanogen 4.2.8
Enoch 1.4.7


From what i read you normally add the swap deal before flashing the rom, i was wondering how i should go about this so i dont mess up the backup files i have for flashing googles 1.6 to cyanogen.
I used this site if you need to see process i used. It be amazing if you could break it down just a little what i need to do so i can get this working from what i gather it should increase phone performance a decent amount. =)

http://wiki.cyanogenmod.com/index.ph...to_CyanogenMod

Thanks in advance =)