You do not have to call every day. There are two options. One is an automatic waitlist that will be filled if it meets your requirements without MS calling you. You will just get the confirmation in the mail. The other requires MS to call you and confirm. Which one did you set up with MS when you made the wait list request?
It wouldn't hurt to call every couple of weeks just to see how things are going. Rememeber that the wait list expires at 30 days out and you will have to call to keep it going up to 7 days before you arrive.
HBC