Maybe telling how they felt and what they said inside while they spoke to the audience.
The dramatic irony lies in the way that we know just as macbeth's himself knows
“And therefore think him as a serpent’s egg / Which, hatched, would as his kind grow mischievous, / And kill him in the shell.”
In these lines Caesar is being compared to a serpent's egg. He states that if the egg hatches the serpent will become troublesome and that it's better to kill the serpent while it's still in its egg. This way the serpent will not pose a problem as it will never get the chance to become dangerous. Brutus makes this comparison between Caesar and the serpent's egg to show that they should kill Caesar before he grows mischievous.
