You find a pair of items that you both like. Maybe it's a sweater for you, and a keychain for him. Or a pair of rings. Or a necklace. Don't think it matters much. But you pool them together and you get out your spoons and you make a declaration to adopt the other. From then on, you've got a connection to them as long as you're holding the item. It's a pleasant connection, like being hugged by them.

Talk to him. I know you've got it in you, Kaeya.