Prophet (s.a.w.) said: "Whoever does not intend to fast before dawn, there is no fast for him." (Al-Tirmidhi) "Whoever does not intend to fast from the night before, there is no fast for him." (Al-Tirmidhi)
The place of intention is the heart and to utter it verbally is not established from the Prophet (s.a.w.) or his companions, may Allah be pleased with them. Thus one should make intention in ones heart before going to sleep.
The time for beginning and ending the fast.Fajr
Eat and drink, until the white thread of dawn appear to you distinct from its black thread; then complete your fast Till the night appears(Quran 2:187)
ii) The meal that is taken before the fajr is called Suhoor (predawn meal)
We should make sure that we eat and drink something at Suhoor, and that we delay it until just before the adhanof Fajr.
The Prophet [an error occurred while processing this directive] (s.a.w.) said "The distinction between our fasting and the fasting of the people of the book is the taking of the pre -dawn meal (Suhoor)" (Muslim)
The Prophet (peace and blessings of Allah be upon him) said: " Have Suhoor, for in Suhoor there is blessing (barakah)." ( Al-Bukharee)
It is also guidance of the Prophet (s.a.w. ) to delay the Suhoor meal until just before the true fajr. (note along with no eating or drinking whilst fasting. one can not have sexual intercourse with spouse. kissing and hugging is allowed but if such close contact causes ejaculation then this will break the fast. Also swallowing saliva of some one else invalidates the fast.
3 The time to breaking the fast (Iftar).
This time is as soon as Maghrib Starts (after sun has set). If you are in the Masjid or close by and hear the Athan for Maghrib prayer then it means you can now break your fast.
One should hasten to break the fast because the Prophet (s.a.w.) said: "The people will be fine so long as they do not delay iftar." ( Al-Bukharee). He (s.a.w.) also said "My Ummah will not cease to be upon my Sunnah as long as they do not await the stars when breaking the fast" (Ibn Hibban). So as soon as Maghrib begins (i.e. if you are in the Masjid and Athan is said) one should start to break the fast immediately.
Break the fast in the manner described in the hadith narrated by Anas (s.a.w.)may Allah be pleased with him): "The Prophet (s.a.w.) used to break his fast with fresh dates before praying; if fresh dates were not available, he would eat (dried) dates; if dried dates were not available, he would have a few sips of water." ( Al-Tirmidhi)
ALLAAHUMMA LAKA S'UMTU WA A'LAA RIZQIKA AFT'ARTU WA A'LAYKA TAWAWKKALTU
O my Allah, for Thee, I fast, and with the food Thou gives me I break the fast, and I rely on Thee