O Allah, illuminate my grave for me and make it spacious. — The Hereafter
اللَّهُمَّ نَوِّرْ لِي قَبْرِي وَوَسِّعْ لِي فِيهِ
Transliteration: Allaahumma nawwir lee qabree wa wassi' lee feeh
Translation: O Allah, illuminate my grave for me and make it spacious.
Reference: General supplication