Ghufaylah Prayer is recited in the period between the Sunset (maghrib) and the Evening (`isha’) Prayers.
This prayer consists of two units
In the first raka’ah you should recite, after Surah al-Fatihah, the following verses (Surah al-Anbiya’ 21:87-88):

وَذَا ٱلنُّونِ إِذْ ذَهَبَ مُغَاضِباً

wa dhā alnnūni idh dhahaba mughāḍiban
And (mention) Dhu’n-Nun (Jonah), when he went off in anger

فَظَنَّ انْ لَنْ نَقْدِرَ عَلَيْهِ

fazanna an lan naqdira `alayhi
and deemed that We would not suppress his sustenance.

فَنَادَىٰ فِي ٱلظُّلُمَاتِ

fanādā fi alzzulumāti
But he cried out in the darkness,

انْ لاَ إِلٰهَ إِلاَّ انْتَ سُبْحَانَكَ

an lā ilaha illa anta subḥānaka
“There is no god save You. Be You Glorified!

إِنِّي كُنتُ مِنَ ٱلظَّالِمِينَ

inni kuntu min alzzālimina
Lo! I have been a wrongdoer.”

فَٱسْتَجَبْنَا لَهُ وَنَجَّيْنَاهُ مِنَ ٱلغَمِّ

fastajabnā lahū wa najjaynāhu min alghammi
Then we heard his prayer and saved him from the anguish.

وَكَذٰلِكَ نُنْجِي ٱلْمُؤْمِنِينَ

wa kadhalika nunji almu’minina
Thus do we save the believers.
In the second unit, you should recite, after Surah al-Fatihah, the following verse (6:59):

وَعِنْدَهُ مَفَاتِحُ ٱلْغَيْبِ

wa indahu mafātiḥu alghaybi
And with Him are the keys of the Invisible.
لاَ يَعْلَمُهَا إِلاَّ هُوَ
la ya lamuhā illa huwa
None but He knows them.

وَيَعْلَمُ مَا فِي ٱلْبَرِّ وَٱلْبَحْرِ

wa ya lamu mã fi albarri walbaḥri
And He knows what is in the land and the sea.

وَمَا تَسْقُطُ مِنْ وَرَقَةٍ إِلاَّ يَعْلَمُهَا

wa mã tasquțu min waraqatin illā ya `lamuhā
Not a leaf falls but He knows it,

وَلاَ حَبَّةٍ فِي ظُلُمَاتِ ٱلارْضِ

wa lā ḥabbatin fi zulumāti al- ardi
not a grain amid the darkness of the earth,

وَلاَ رَطْبٍ وَلاَ يَابِسٍ

wa lā raţbin wa lā yābisin
naught of wet or dry

إِلاَّ فِي كِتَابٍ مُبِينٍ

illā fi kitābin mubinin
but (it is noted) in a clear record

After that, you should raise your both hands for Qunut, saying:

اَللَّهُمَّ إِنِّي اَسْالُكَ بِمَفَاتِحِ ٱلْغَْيِبِ

allāhumma inni as’aluka bimafātiḥi alghaybi
O Allah, I beseech You in the name of the Keys of the Invisible (world)

ٱلَّتِي لاَ يَعْلَمُهَا إِلاَّ انْتَ

allati la ya`lamuhā illā anta
that none knows save You;

اَنْ تُصَلِّيَ عَلَىٰ مُحَمَّد وَآلِهِ وَ انْ…

an tuşalliya`alā muḥammadin wa ālihi…
(please) send blessings to Muhammad and his Household and…
You may then mention your needs. Then, say the following:

اَللَّهُمَّ انْتَ وَلِيُّ نِعْمَتِي

allāhumma anta waliyyu ni`mati
O Allah, You are the source of the graces that I have,
>وَٱلْقَادِرُ عَلَىٰ طَلِبَتِي
walqadiru `alā talibati
You have the power to respond to my request,

تَعْلَمُ حَاجَتِي

ta` lamu ḥājati
and You know my needs;

فَاسْالُكَ بِحَقِّ مُحَمَّد وَآلِهِ

fa-as’aluka bihaqqi muḥammadin wa ālihi
I therefore beseech You in the name of Muhammad and his Household,

عَلَيْهِ وَعَلَيْهِمُ ٱلسَّلاَمُ

alayhi wa ‘alayhimu alssalamu
peace be upon him and them,

لَمَّا قَضَيْتَهَا لِي

lammā qaḍaytahā lī
to grant me my needs.

You may then pray to Him for your personal needs.
After Qunut, complete your Salaah in the regular manner.
It has been narrated that any one who offers this prayer and supplicates Almighty Allah will have his requests granted.