How can a person be divinely supported by God and make sound choices without regret, especially in urgent matters or when الاستخارة (guidance-seeking prayer) is not feasible, and is there a specific method or supplication for that?

The greatest way to attain Allah's guidance (tawfiq), enablement (tasdeed), and inspiration of rectitude (rushd) is through fearing Allah the Almighty (taqwa). For Allah has promised the righteous (al-muttaqin) that He will grant them a criterion (furqan) and a light by which they walk, a way out in this world and the hereafter, victory, a means to attain Allah's reward, an expiation for their sins, and forgiveness for them. As Allah the Almighty says: "O you who have believed, if you fear Allah, He will grant you a criterion and remove from you your misdeeds and forgive you." So, whoever fears Allah will be guided to distinguish truth from falsehood, and to achieve victory, salvation, and happiness in both abodes. Fearing Allah is a cause for ease, success, and Allah's companionship and guardianship. And the servant should strive to perfect his fear of Allah by observing His commands and avoiding His prohibitions, so that he may receive Allah's guidance, enablement, and support.