How to develop churn prediction model for telecom company?

You are right, the most important place to dig is in Customer Care system or better say CRM database. What I want is that what are the steps in an order way to design the prediction model and of course which model best suits for analyzing telecom data. Step1: find as much attributes in telecom data as you can, and make a dataset of those data. Jan 2013, Feb 2013, Mar 2013) and extract those customers in this period of time (Jan, Feb and March) which leave the company (Am i right?) and then by having this dataset of churned and unchurned customers in Jan and Feb and March 2013 we can go to step 2 for further processes to finally could build a model which can predict the churn rate of customers in April 2013(Am i right? I want to know whether I am doing right or not?).