Al-Imām ibn Battāl [may Allāh have mercy on him] said:
“Whomsoever has *abundant sins* and desires for Allāh to remove these sins from him without burdening himself, then let him seize the opportunity and remain seated in his place after the completion of prayer, in order that he may take advantage of the Angels, whom seek increase in their supplication for him and increase in their invoking for [Allāh’s] forgiveness for him, he who [has abundant sins] is awaiting in hope for his response [from Allāh, Exalted be He].”
Sharh Saheeh ul-Bukhāri, 2/95| Al-Imām ibn Battāl [may Allāh have mercy on him]
"Very easy way to get your sins forgiven"