I'm just confused what you find difficult about it that made you feel the need to ask about it
You kinda just... Do it
You put a screen in place of the head and add other stuff as you see fit
Could be antennas, could be animal ears, could be anything honestly depending on your preference or the lore you have in-mind
I just make screenheads because I think it looks cool. Making a screenhead is pretty much the same as making any other character design
I do recommend adding at least something on the head though otherwise they look... bald.