events between forms

[Crash893]

I have a mdi parent form and a logon form (among others)

I'm trying to create an event that will be triggered from the logon form when the users "logon"

the code i have so far is

in the logon form

public event EventHandler Authenticated;

and in the main form

logon newForm = new logon();
            newForm.Authenticated += new EventHandler(?????????);
            newForm.MdiParent = this;

my two questions are

1) what should i put under the event handler and (makred in ???)
2) and how would i create a "stub" for it in the main form

i.e

private void ???????(object sender, EventArgs e)
        {
           
        }

thanks if you can point me in the right direction