It is recommended (sunnah) to break one’s fast as soon as one is sure the maghrib (sunset) has begun.
It is good to break one’s fast by eating dates, and if not available, then by drinking water. It is good to say the following statement upon breaking one’s fast:
اللهم لك صمت وعلى رزقك أفطرت
which means: <<O Allah, for Your sake I fasted, and with Your sustenance I broke my fast.>> It was narrated from Abu Dawud that the Prophet used to say this supplication upon breaking his fast. It is also good to delay the suhur meal until a time close to the dawn--but to stop eating before the dawn.
Refraining from backbiting, cursing a Muslim, and other sins, is more emphasized while fasting. In committing some sins, the reward of one’s fasting might be lessened or lost. If someone curses another, let the one cursed abstain from responding with a similar curse. Instead, let him say, “I am fasting. I am fasting.”
Paying the optional charity to the poor; reciting the Qur’an; staying in the mosque with the intention of i^tikaf, especially during the last ten days of Ramadan; praying the Tarawih prayer; and inviting others to break their fast on food which you provided are all rewardable acts.
The month of Ramadan is a great opportunity for tone to gain a great deal of reward. Reward is earned by performing this obligation in worship and obedience to Allah, and by performing many of the recommended (sunnah) deeds. Let the person not waste his time during this blessed month.