I don't believe the guidelines give any help on exactly how to notify.  Some people have sent a very brief letter to the home address of the other parent by certified mail return receipt.  The return receipt is your proof that you did provide notice.  Make sure you keep copies of everything just in case.

I don't think the court has mandated any certain method.  I suppose an email would work just fine if neither party has a history of lying in court.  What's to say someone's email wasn't hacked or someone else used the email and responded to you.  Legally, the only methods of service that I know of are fax (but only if that person has elected to receive service by fax), service by the sheriff, and service by the USPS or some other carrier  as long as signature is required and a return receipt is requested.  Refer to statue 60-303.