If your bow is that off you need to start from scratch. The others guys are right but I would go further.

Put an arrow in you nock and make it is center to the riser and level on the string. (Use another arrow as a comparison)

Then paper tune. Then Nock tune. Then change your sight to match POI. Then you can even do a walk back to fine tune your rest.

Heres an in depth guide.

http://www.archerytalk.com/vb/showthread.php?t=1399457

I dont go crazy, but I atleast try to get my nock tune correct.