How do you ensure your prayer is sound and accepted by our Lord?

The prayer is valid when its conditions, pillars, and humility are fulfilled, and it is nullified only by omitting any of these or by performing an invalidating act. As for acceptance, it is an unseen matter conditioned upon sincerity, as Allah states: "And they were not commanded except to worship Allah, [being] sincerely obedient to Him, inclining to truth, and to establish prayer and to give zakat. And that is the correct religion." And the Prophet (peace be upon him) said: "Indeed, actions are by intentions." A Muslim should strive to ensure that his prayer is purely for the sake of Allah, free from showing off, and remain fearful and apprehensive of his deeds being rejected, seeking forgiveness from his Lord for his shortcomings, and having good expectations of Him, as Allah says: "And those who give what they give while their hearts are trembling because they know that they will be returning to their Lord."