Assalamu Alaykum. I use to do 20 Rakats + 3( Shafa & witr ) for Salatul Layl. So, the 20 Rakats are 10 Prayers of 2 Rakats, and the 1rst Rakat I use to recite FATIHA and IKHLAS, 2nd Rakat: FATIHA and KAFIRUNA The Shafa prayer: 2 Rakats; 1rst FATIHA and NASS, 2nd FATIHA and FALAKHI. The Witr prayer, one Rakat: FATIHA, plus 3 IKHLASS plus FALAKHI, plus NASSI. Correct me please if I'M WRONG. But, I WOULD LIKE TO KNOW how to pray the Writr supererogatory prayer(13 Rakats after Isha) and what are the Surats to recite. THANK-YOU

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.

What you used to do, which is praying 20 Rak’ahs for the night prayers, is permissible. In regard to abiding by the recitation of a given Chapter, then this should not be done as there is no evidence for it. Rather, you should recite any Chapter or verse without specifying any recitation (of a given Chapter or verse) for any Rak’ah, unless there is evidence for this. For more benefit, please refer to Fataawa 84999 and 84515.

Moreover, it is more appropriate to abide by the order of the Mus’haf (the Arabic text of the Quran) when reciting in the prayer. For instance, if you want to recite Chapters 113 and 114, then you should recite Chapter 113 in the first Rak’ah because Chapter 113 comes first in the Mus’haf.

On the other hand, the Sunnah in Witr prayer is to recite Chapter Al-A’la [Quran 87] in the first Rak’ah, Chapter Al-Kaafiroon [Quran 109] in the second Rak’ah, and Chapter Al-Ikhlaas [Quran 112] in the third Rak’ah. For more benefit, please refer to Fatwa 84482.

Nonetheless, whatever you recite in the Witr prayer or in the night prayer is permissible and there is nothing wrong with this. However, the longer the recitation is, the better. In addition, it is permissible for you to recite from the Mus’haf as clarified in Fatwa 83531.

Finally, in case you want to pray the Witr as 13 Rak’ahs, then you should pray in twos, and then finish your prayer with one Rak'ah. For more benefit, please refer to Fatwa 83333.

Allaah Knows best.