One should say: “Allahumma ighfir li warhamni wajburni wahdini warzuqni (O Allah, forgive me, have mercy on me, enrich me, guide me and grant me provision).” (Narrated by al-Tirmidhi, 284; Ibn Majah, 898 – from the hadith of Ibn 'Abbas; classed as sahih by al-Albani in Sahih al-Tirmidhi. And there are other du'as.)