Know! O my Muslim Brother, that Allaah has made fasting obligatory upon us so that we worship Him doing so; (therefore) so that your fast is acceptable and beneficial (to you) be aware of the following:
v 1) Be wary of protecting your prayers: Many people who are fasting are slack in maintaining their prayers despite it being a pillar of the religion, and leaving it is from (the acts of) kufr;
v 2) Maintain good manners: Be wary of falling into kufr and cursing the religion, and ill manners towards the people, particularly whilst fasting. Fasting purifies the inner self and does not lead to ill manners, and kufr renders the Muslim outside the fold of the religion;
v 3) Do not speak unnecessarily even if you are joking, as this will reduce the reward of your fast. Take note of what the Messenger of Allaah (sal-Allaahu 'alahe wa sallam) said:If any of you are fasting, then abstain from ignorant and indecent speech that day; and if anyone curses you or strikes you, then say: I am fasting; 
v 4) Benefit from the fast by leaving off smoking, which causes cancer and ulcers; Try to maintain your willpower and leave off smoking in the evening just as you left it during the day. As a result, you will be better off in health as well as financially;
v 5) Be wary of divulging in excessive eating at the time of breaking the fast, as it can result in ruining the benefit of the fast and harming your health.
v 6) Do not go to the cinema or watch television, so that you do not see that which will spoil your fast and ruin its effect;
v 7) Do not go to sleep too late and as a result miss out on the sahoor (pre-dawn meal) and the Salaatul-Fajr. Try to maintain an early start to your work, as the Messenger of Allaah (sal-Allaahu 'alayhe wa sallam) said:O Allaah bless my Ummah in that which they maintain of an early start; 
v 8) Increase in giving in charity to your relatives and those who are needy; visit your relatives (to maintain family ties) and clear up any disputes and misunderstandings that may exist;
v 9) Increase in the remembrance of Allaah and recite the Qur.aan, listen to it and reflect upon its meaning and act according to it. Go to the masaajid to listen to beneficial talks; and doing the i'tikaaf in the masjid during the last ten days and nights of Ramadhaan is from the Sunnah;
v 10) Read around the subject of fasting so as to learn its rulings. You will then come to know that eating and drinking forgetfully does not break the fast. Also, having sexual intercourse during the night does not prevent anyone from fasting;
v 11) Maintain the fast of Ramadhaan and prepare your children to fast as soon as you feel they are capable, and beware of breaking the fast without an Islaamically valid reason. Whoever intentionally breaks his fast any day then he is required to make up that day and repent;
v 12) Beware O my Muslim brother from eating (and drinking during the day) in Ramadhaan, and beware of openly doing so in front of the people, for indeed doing so is tantamount to fearlessness of Allaah, making a mockery of Islaam, and brazenness in front of the people. So know that whoever does not fast, then he has no right to celebrate the 'Eed since 'Eed is a major celebration upon the culmination of the fasting and anticipation for the acceptance of one's worship.
 [The authenticity of this narration has been agreed upon by al-Bukhaaree and Muslim]
 [Saheeh, transmitted by Ahmad]