This is what I found the most effective way to debug.

  1. Read the description of the bug carefully.
  2. Write the tasks needed, on a piece of paper.
  3. Go to nearest food stall or restaurant.
  4. Treat yourself some good meals and nice coffee.
  5. Enjoy the view of your office and relax.
  6. Sit down in a sofa.
  7. Start gathering the logs and info needed from ANY source.
  8. Start exploring the logs or profiling.
  9. Find the damn root cause. If not found go back to 4.
  10. Fix them once and for all.

Any other methods? Let me know.