1) The obligatory deed is more beloved to Allah than the nafil deed. Make up any missed days before fasting the six days of Shawwal. The hadeeth "Whoever fasts Ramadan then follows it with six days of Shawwal, it is like fasting for a lifetime." implies that one should complete the obligatory fasts first. That will discharge one's duty and is also being on the safe side.
2) Be grateful and seek forgiveness: The servant is always either the recipient of a blessing from Allah, in which case he is in need of gratitude; or he is the perpetrator of a sin, in which case he is in need of repentance. (From Majmoo' al-Fatawaa).
3) A recompense the like thereof: The Prophet (peace be upon him) said: "Whoever calls people to right guidance will have a reward like that of those who follow him, without that detracting from their reward in the slightest. And whoever calls people to misguidance will have a burden of sin like that of those who follow him, without that detracting from their burden in those who follow him, without that detracting from their burden in the slightest." (Muslim)
4) If Allah has accepted a person's Ramadan, and he benefited from that spiritual training, and he continues to obey Allah, then he has joined the caravan of those who remain steadfast and respond to Allah. He says (interpr. of meaning) : "Verily those who say: 'Our Lord is Allah (Alone),' and they stand firm, on them the angels will descend (at the time of their death) (saying) : 'Fear not, nor grieve! but recieve the glad tidings of Paradise which you have been promised!'" [Fussilat 41:30].
5) From the signs that a person's deeds are accepted is that he or she has improved in obedience to Allah. Allah says (interp. of meaning) : "And remember when your Lord proclaimed, 'If you are grateful, I will surely increase you [in favor] ..... " [Ibrahim 14:7]. Arighteous deed followed by a righteous deed, a hasanah followed by hasanah.
