SOURCE 1: https://www.google.com/amp/s/writefortheking.wordpress.com/2017/07/10/how-to-write-stuttering/amp/
SOURCE 2: https://www.healthline.com/health/stuttering#typesWhen people write stutters from what I have seen, they exaggerate the character's speech.
》EX: ' I-I-i saw h-him today a-at the s-store.'
Based off of source one {By Gabrielle Massman}, one should keep the stutters to a minimum, 1 stutter per line (2 if you can pull it off well), 3, maybe in a paragraph.
You can add a stutter and not make it annoying, remind your viewers that the character has a stutter subtly, instead of using a stutter say " [stuttered, can be put here.] ( Insert pronouns/character name) [stuttered, OR here]"
》EX: ' I saw him today at the store.' Lukas stuttered.
As source two {By Rachel Nall} stated, constants like 'K', 'G', and 'T' are repeated, and that a stutter may cause stress which can be demonstrated by a show of these symptoms:
× The use of "um" and "uh"
× Repeated words/phrases
× Word rearrangement
× Physical
+Excessive Blinking
+Tension in face or upper bodyA person who is stressed is more likely to stutter more than a person who is not stressed at all.
Stuttering as a speech disorder, has several causes and is not very common.
Some children can have the option for speech therapy.=IF YOU HAVE SOMETHING YOU WANT ME TO CORRECT, PRIVATE MESSAGE ME. IF YOU WANT TO COMPLAIN WITHOUT RESOLUTION, KEEP IT TO YOURSELF=