글쓰기 original character fanfiction! Advice?

i have a story idea for you. an American exchange student at Hogwarts. now what do 당신 think of that?? also, what is a Mary sue?

I would just say try your best and that's all 당신 can do.

About plot issues: maybe plan it out in advance and insist that 당신 stick to it, instead of adding whatever 랜덤 ideas that come to 당신 when you're writing.

About Mary Sues: make sure that 당신 give the OC enough weaknesses. And real weaknesses too, ones which make him 또는 her make mistakes, not just cutesy ones. For each OC, list the weaknesses to make sure they're enough. Also, check how 당신 describe him 또는 her. If you're being really flowery about how beautiful he 또는 she is, 또는 how perfect 또는 how much everyone else loves him 또는 her, you'll want to cut that out.