How can one practically repent from relapse, smoking, and music?

Do not despair of Allah's mercy, for sincere repentance erases all sins. Correct repentance is the heart's regret and the resolve not to return to the sin before facing the realities of the Hereafter. Beware of being defeated twice by abandoning obedience after sinning. The major problem is not the sin itself, but abandoning acts of obedience and surrendering to Satan. Indeed, a punishment for a sin is another sin that follows it, because it leads to a loss of confidence and to persistence in disobedience and abandonment of acts of obedience. To overcome this, persist in acts of obedience and multiply good deeds, for good deeds erase evil ones. Do not allow sin to affect the course of your obedience, and be careful not to move from one sin to another. Maintain your daily acts of worship such as Qur'an recitation, prayer, remembrance of Allah (dhikr), and supplication (du'a), for they are your spiritual provisions.