To learn from your writing mistakes, you need to move beyond simple correction and rewrite. Instead, actively analyze each error, group them by type, and then drill those specific patterns until they become automatic. This turns passive correction into active skill building.
Your current method of correcting and rewriting is a good starting point, but it is not enough because it does not force your brain to internalize the correct form. The key is to make the correction effortful and to target your weak areas systematically.
First, after getting your writing corrected, do not just rewrite the whole sentence. For each mistake, write the incorrect version and the correct version side by side. Then, write a brief rule or explanation for the correction in your own words, in your target language if possible. For example, for a gender error, write: "le livre (masculine) because most nouns ending in -re are masculine." This forces you to understand the rule, not just copy the fix.
Second, keep a personal error log. Create a simple spreadsheet or notebook with columns: date, error type (e.g., gender, verb conjugation, preposition), the incorrect phrase, the corrected phrase, and the rule. Review this log weekly. This helps you see patterns and track your progress. You will notice that you keep making the same three or four types of mistakes, which is normal and valuable information.
Third, design targeted drills based on your error log. If you struggle with masculine and feminine, create a list of 20 nouns you often get wrong and test yourself daily with flashcards (physical or digital) that require you to state the gender before the meaning. For verb conjugation, write out full conjugation tables for the tenses you misuse, then cover them and try to recall them. Do this for 10 minutes each day, focusing only on your weak spots.
A concrete next step: take your last corrected piece of writing. Identify the three most common error types. For each type, create 5 to 10 practice sentences that specifically target that pattern. Write them, check them with a grammar resource or a tutor, and repeat until you get them right without thinking. Only then move to a new piece of free writing.
Honest tradeoff: this method requires more time and mental effort upfront than just rewriting. But it is far more effective for long-term retention. You might feel slower at first, but you will make fewer repeated mistakes. There is no shortcut to internalizing grammar; you must deliberately practice the patterns you find difficult.
Remember that writing is a skill that improves with deliberate, focused practice. By turning each correction into a learning opportunity, you will steadily reduce your errors and gain confidence.