You must perform a ghusl (full shower) in order to pray after:
1. You perform sexual intercourse.
2. Your menstruation ends.
3. Your postpartum bleeding ends.
4. You give birth to a child, even if it was without bleeding.
5. Your maniyy is emitted
How to Perform Ghusl
After removing any najas from the body, the ghusl is performed in the following way:
1. It is obligatory for you to intend in the heart to perform the obligation
of ghusl when the water first touches your body.
2. It is obligatory to wash the whole body with water, including all of the
hair. It is recommended to to do this three times.
When performing either the wudu' or ghusl, all substances which prevent water from reaching the parts to be washed and wiped must be removed.
Examples are: nail polish on fingernails and toenails and waterproof mascara.