I'm making a comic where a character is scared and is hyperventilating. What should I write to make it as if they're panting/gasping?
Apart from huff and puff suggested in the comments:
You could also use:
huh and phoo (even thought dictionaries don't list this meaning for the first one, and don't list the second one at all, they sound pretty short-of-breathy):
Verbs such as: gasp, pant or whiff can be put into small clouds instead of onomatopoeia.