Look in the tutorials for the simple evocation guide. Adapt it for the number of evocations you need to do.
Simple English Demonic Evocation Guide - New Magician Help & Introductions - Become A Living God
You can use their name or anything else that you have attached to that person (username, name, place-of-birth). You know who they are. The Deities will know who you’re talking about. Don’t over-think it.
Unless you have permission from them both for the level of action you’re taking, then you are. Fortunately, we don’t really look down on that here, but let’s not sugar-coat it.
Finally, please keep in mind that if this is a test that one or the other is supposed to go through for some reason, this may not work or may be diminished. Doesn’t mean you shouldn’t try again or similar, if you didn’t like your result. It may mean you should contact the deities first and make sure they’re onboard with the action and will help ensure its success. Some people use tarot for this. If I’m going to call upon a Deity, I ask that Deity. So, regardless, you’ll want a means of communication.
Hope it helps.