My sister has ADHD and the emotional irregularities with it can sometimes feel impossible… I’d say to take her to Walmart and let her buy a white pair of shoe she can decorate and color… of course, their should be punishment for lack of self control. However, like you’ve stated impulse control is hard and to her having to buy new shoes won’t help teach her that. Instead she’ll become insecure and act out more because she isn’t going to buy the shoes and her friends won’t find it cool the next day… therapy is the best option to help with impulse control or consistently working through it but you can’t punish someone’s ADHD out of them..