i want a small paragraph on a most memorable day of my life

This answer needs to be framed based completely on your own personal experiences, ideas and perceptions. However, I would cite a few points over here of what should be kept in mind while writing this paragraph.

• Introspect for a while on what made the day special. Was it a surprise you received on your birthday, or a chance meet with your friend after a long time or a road trip to the Himalayas.

• Write a detailed description of the day and the specific reasons of what made it special.

• Take 5 minutes to recollect every little detail to make the account very interesting and mind gripping.

• Pen down your ideas randomly and attractive words on a rough sheets and then organise them in the correct sequence to make sense.

• Never rush with the entire process. Exemplify its beauty by focussing more on your feelings and emotions attached to the event or the day and less on the other features like the month, the date, the colour of the sky or the surroundings at that point of the time.

• When you are finished, read your work again. Add anything especial that you think it's missing. Your account is done! Congratulations! Great job!