From what is istinja' obligatory?
It is obligatory to make istinja' from every wet material emitted from the eliminatory outlets, like urine or feces.
Istinja' is performed using pure and purifying water or a solid, dry, uprooting and unrespectable material, like a stone or paper.
Performing istinja' by water: When cleaning oneself from feces one pours the water on the outlet and rubs with one’s left hand until the najas-filth is removed. This makes the place tahir.
Performing istinja' using rocks and the like (paper): If one makes instinja' using a solid, dry, uprooting, pure, unrespectable material, such as a rock (or paper), one wipes the outlet three times. If the three wipes are not enough to clean the area, one wipes more until the place becomes clean. One may use three wads of tissue or the like. Without using water, it is not enough to wipe less than thrice, even if the place becomes clean.
For the istinja' without water to be valid, it is a condition that it takes place:
1- Before the najas-filth dries. If the emitted najas-filth dries, then using water becomes mandatory.
2- Before the najas-filth spreads. If the najas-filth spreads beyond the original place from which it was emitted, then using the water becomes obligatory.
It is recommended to enter the bathroom with the left foot, and to leave it with the right foot; contrary to the way you enter the masjid. It is recommended (sunnah) to enter the masjid with the right foot first, and to leave it with the left foot.
It is recommended (sunnah) upon entering the bathroom to say:
Bismillah. Allahumma inni a^udhu bika minal-khubuthi wal-khaba’ith.
Which means: “[I enter the bathroom] with the Name of Allah. O Allah, I seek refuge with you from the male and female devils.” This provides protection from the eyes of the jinn.
After leaving the bathroom, it is also recommended to say:
Ghufranak. Al-hamdu lillahi-lladhi adh-haba ^annil-adha wa ^afani.
Which means: “I ask You (Allah) for forgiveness. Praise and thanks be to the One (Allah) Who took the harm away from me and granted me good health.”