1. Spending quality time together
Giving your time and undivided attention to your parents is one of the most important ways in which you can honour them. No matter how busy or hectic your life is, spending quality time with them on a regular basis will make them feel special and important (especially if you don't live with them).
And if you can't visit your parents in person, be sure to call and message them often to ask how they are and to ask if they need anything.
Note: When spending time with your parents, always try to give your full and undivided attention to them. Being glued to your phone whilst they are trying to have a conversation with you is disrespectful and will undoubtedly make them feel as if they are not important to you.
2. Making sincere dua
Always remember your parents in your duas (which you should strive to make on a daily basis). Specific examples of duas you can make include asking Allah (swt) to grant them good health, forgiveness, strong imaan, and a long and prosperous life.
Also remember to ask Allah (swt) to ease any difficulties that they may be facing and to protect them from all harm.
There are also powerful Quranic duas as follows:
1. Surah Al-Israh, Verse 24
Transliteration: Rabbi irhamhuma kama rabbayanee sagheera
"And lower to them the wing of humility out of mercy and say, "My Lord, have mercy upon them as they brought me up [when I was] small."
2. Surah Nuh, Verse 28
Transliteration: Rabbi ighfir lee waliwalidayyawaliman dakhala baytiya mu/minan walilmu/mineena walmu/minatiwala tazidi aththalimeena illatabaran
"My Lord, forgive me and my parents and whoever enters my house a believer and the believing men and believing women. And do not increase the wrongdoers except in destruction.”
3. Surah Ibrahim, Verse 41
Transliteration: Rabbana ghfir li wa li wallidayya wa lil Mu’mineena yawma yaqumul hisaab
Translation: “Our Lord! Forgive me and my parents, and (all) the believers on the Day when the reckoning will be established.”