Continuos rotation?

hello everyone im making a robot, and ive accidently bought my self non-continous servos. so i was on my way to convert them yo continous rotation and reading all the how-to's it says you need to use a servo controller to set the servo to the center position before beginning, but i do not have a servo controller. please tell me if i can just do this without setting it im just making a  small r/c or autonomous robot. if i need to can i just go ahead and skip that step do everything else and then wait for my arduino and motor shield to come in and then set it to center position? thank you i would rather not spend another 30 dollars to buy more motors.

I’ve hacked a lot of servos.

I’ve hacked a lot of servos. There is no need to center the servo first. Just replace the potentiometer with 2 resistors as shown here: