So I just wired a pickup into my guitar in parallel just like this http://www.dimarzio.com/sites/default/files/diagrams/1hum1vol1tone_parallel.pdf

I used 2 cts pots. But for some reason the volume knob doesn't work. I took the time to check 2 other pots and wire them up the same,and they worked fine,the volume went up and down. but then I re installed them again on the CTS ones and the volume doesn't work for crap. Why is this? Broken pot?
on the volume knob? I think so. I bent it back and soldered it to the pot.but i'm not sure if I did it perfectly,if that's whats causing the problem ill double check it
Recheck your work. Anytime you build something and it doesn't work, the first rule is to grab the drawing/schematic and recheck your connections. Also check for unintentional shorts, cold solder joints, or anything else that might cause it not to work.

Best of luck