Before you call, consider this:

Where are you ranked and does knowing where the list is benefit you in anyway? If you're ranked in the 350's or higher regardless of local your're never going to get called so don't waste your time, try again elsewhere or another career. If you're lower than 30, call so you can gauge where they are, but don't call weekly. If you're in the 50's- 120's calling every other month might be your best option.

Don't let this distract you from your normal life. There are many threads here with tons of useful information.

There is nothing you can really do to prepare for the call. You can be the next on the list and wait three months before they call you. You could be 30th on the list and wait two days.

Companies don't like to hire off the list. It is a last resort. You are a last resort. You will be treated as such.