What are the rules of istinja and toilet etiquette?

“It is permissible to make istinja with water of any temperature, however the water should not be so hot that it burns or causes harm to the body.i”

“It is permissible to use wet wipes or tissues for Istinjaa (ritual cleansing). However, it is preferable and Sunnah to also use water to ensure thorough cleanliness.”

“Water should be used at the time of istinja. One should not suffice on using toilet paper. If traces of impurity are left on one's body due to not using water and it exceeds the amount of the circumference of one's inner palm, then the Salaah will not be valid.”

“It refers to urine and stool only as the word ‘Istinja’ is generally used for urine and stool. The Mas’ala is as follows: If urine or stool doesn’t exceed the place of exit (that is the front or back private part), then using water to wash the private part is Sunnah (and not obligatory).”