Answer: One should show courtesy to one's parents by:

1. Obeying them in whatever does not involve a sin

2. Serving them

3. Helping them

4. Fulfilling their needs

5. Supplicating for them

6. Speaking politely with them, as it is impermissible to say even "Uff", which is the slightest word expressing annoyance.

7. Smiling at them and refraining from frowning at them

8. Not raising one's voice when talking to them, listening to them without any interruption, and not calling them by their names; rather, one should say "dad" and "mom"

9. Seeking permission before entering when they are in their room

10. Kissing their heads and hands