In first few months I got much comments on my code after code review. Later on I started building that mindset. It help me a lot,

Let me share with you few techniques

1. Mindset (start building that mindset).

2. Use Exceptions handling, read error messages, log errors.

3. Try test your core logic, all possible ways (write multiple inputs, don't test your code on same input again and again).

4. Figure out break points. And print messages on all breakpoints.

5. Believe that you are human and you have made errors. start finding out them.

6. Start testing your code at the beginning(line by line).

7. Also Take break, have some coffee and let your logic run in background of your mind, and then get back.

8. In all this you need a lot of patience.

Keep Learning!!