The website jumpseatinfo.org has specific instructions for how to list for the different carriers. You should be able to jumpseat as soon as you are in CASS, which I've heard is a week or two for new hires.

The myIDtravel site is for zed fares. Zed's are standby tickets you buy on other airlines. Your spouse and dependents can buy zed fares as well. You can't start using zed fares until 6 months on property.