私の英語が間違っていたら、訂正してください。って英語でなんて言うの？

It can be a challenge to speak a new language. But when you want some help to improve your language skills, it is always good to ask for help when you have the opportunity.

A few expressions you could use to ask for help and corrections are:

1) "If I make a mistake, please correct me."
2) "If I say something incorrectly, please fix my mistake."
3) "Could you help me by fixing my mistakes?"

When you want to explain to someone that you'd like them to correct you when you speak English, then you can say it in the following ways:
-Please correct my English if I make any mistakes
-Please correct any grammatical mistakes I make when I speak.
-Please correct any pronunciation mistakes I make when I speak

Any of these sentences can be used to ask someone to correct the mistakes that you made.

1. If I say something incorrect, please let me know.
   私が間違ったことを言うなら、私に知らせてください。

2. Please don't hesitate to correct my mistakes as soon as you hear them.
   私の間違いを聞くとすぐに間違いを訂正してください。

   Whenever we use the phrase "please don't hesitate" it means please don't delay or "please feel free to do something."

If you would like your teacher to take note of any mistakes you make and correct them you may ask the teacher to listen for any mistakes and then correct you after you are done speaking you may also let the teacher know if you prefer being corrected immediately or after you are done speaking. You may ask in the following ways;
Please correct my pronunciation and grammar if I make mistakes.
Please give me immediate corrections if I make any mistakes.
(on the spot corrections-immediate corrections)
Please help me by correcting my mistakes today teacher.

If you are wanting to be corrected then you could say 'Please correct me if i make a mistake' if you add 'my English' you are explaining what you want them to correct
Another way of saying this is 'If i make a mistake with my English, please correct me!'
These are all good examples to express what you mean

You can ask as a statement of fact. You tell me if I make a mistake, or as a question by starting the sentence with Can, Can you tell me if I make a mistake.