Requirements of Ramadhan

The Holy Prophet (peace and blessings of Allah be upon him) has given guidance to the Muslims for each and every thing. He has given detailed instructions on when to start the month of Ramadhan and how to spend time during this month.
Beginning and Ending of Ramadhan: Hazrat Ibn Umar (may Allah be pleased with him) has narrated that: "I heard the Holy Prophet (peace and blessings of Allah be upon him) saying that you should start fasting when you see the moon for the month of Ramadhan and stop fasting when you see the new moon" (Sahih Bukhari, Kitab-ulSaum).
Forgetfulness while fasting: The Holy Prophet (peace and blessings of Allah be upon him) has said: "if some mistakenly eats while fasting he should complete his fast till the evening because surely Allah made him eat and drink" (Sahih Bukhari, Kitab-ul-Saum).
Importance of eating breakfast: Anas relates that the Holy Prophet, peace be upon him, said: "Take breakfast before the fast begins; there is blessing in breakfast" (Bokhari and Muslim), Zaid ibn Thabit relates: We ate breakfast during Ramadhan with the Holy Prophet, peace be upon him said: "The difference between our observance of the fast and that of the People of the Book is eating of breakfast" (Muslim).
Etiquettes of Sehri (food taken at dawn): Sehri is a blessed meal. The Holy Prophet (peace and blessings of Allah be upon him) has said: "This is truly a blessing. One strengthens in oneself the habit of getting up early in the morning and to worship Allah and one can offer humble prayers to Him." The Holy Prophet (peace and blessings of Allah be upon him) also said: "Eat Sehri as there are blessings in eating Sehri" (Sahih Bukhari, Kitab-ul-Saum).
At time of Iftar (opening the Fast): There are some times during the day that are more helpful and assist in prayers being answered, Allah accepts more prayers when the fast is opened. In one saying the Holy Prophet (peace and blessings of Allah be upon him) has reported to have said: "No prayer is rejected at the time of the opening of the fast that is offered by someone who has been fasting" (Sunan Ibn Maja, Al-Abwab Al-Dawat).